An electromagnetic wave absorbing heat conductive composition is used to form an electromagnetic wave absorbing heat dissipating article that is placed between a heat generating electronic component which, when operated, generates heat, reaches a temperature higher than room temperature and acts as an electromagnetic wave generating source, and a heat dissipating component. The composition is non-fluid at room temperature prior to operation of the electronic component, but acquires a low viscosity, softens or melts under heat generation during operation of the electronic component, to fluidize at least a surface of the composition so that the composition substantially fills any gaps between the electronic component and the heat-dissipating component.

Circuit design for the latest electronic equipment, including TVs, radios, computers, medical devices, office equipment and telecommunications devices, has become increasingly complex. For example, integrated circuits which contain the equivalent of several hundreds of thousands of transistors are now manufactured for these and other kinds of equipment. This rise in design complexity has been accompanied by a parallel trend toward the fabrication of ever smaller electronic components. That is, manufacturers are finding ways to fit larger numbers of such components on steadily shrinking device footprints while at the same time continuing to reduce the dimensions of the device.
Because heat generated by the various working components causes device malfunctions and inoperability, methods for effectively dissipating heat generated by electronic components are needed.
Such problems associated with heat generation are exacerbated by the increasing levels of integration being achieved in electronic components—particularly central processing units (CPUs), drivers, integrated circuits (ICs), memories and other large-scale integration (LSI) devices—which are used in electronic equipment such as personal computers (PCs), digital video disks (DVDs) and cell phones. Another current trend is a shift toward higher operating frequencies for higher performance. This has led to the generation of harmful electromagnetic waves which can cause failure, malfunction or inoperability due to electromagnetic interference between electronic components, and may have deleterious effects on the human body.
Many heat dissipating methods, as well as heat dissipating articles and compositions used in such methods, have already been devised to reduce the heat generated by electronic components. Heat sinks in the form of plates made of brass and other high thermal conductivity metals are used in electronic equipment to hold down the rise in temperature of electronic components therein during use. These heat sinks carry away heat generated by the electronic components and release that heat from surfaces by means of a temperature difference with outside air.
For heat generated by an electronic component to be efficiently transferred to a heat sink, it is necessary that the heat sink be placed in close contact with the electronic component. Because of height differences among various electronic components and component tolerances in the assembly process, a flexible heat conductive sheet or a heat conductive grease is often placed between the electronic components and the heat sink so that heat transfer from the electronic components to the heat sink takes place through the heat conductive sheet or grease. Heat conductive sheets made of materials such as heat conductive silicone rubber are used for this purpose, but a problem with such sheets is their interfacial thermal resistance.
Methods that have been proposed for lowering the interfacial thermal resistance include the use of heat conductive greases and thermosoftening sheets such as those described in JP-A 2000-509209. However, these prior-art greases and sheets serve only as heat dissipating articles, and lack the ability to absorb electromagnetic waves.
Many attempts have been made to shield out electromagnetic waves generated from electronic components. Such efforts have generally involved the use of metals, platings or electrically conductive compositions, but these materials all rely on the ability to reflect electromagnetic waves. Sheets composed of an organic rubber medium, especially chlorinated polyethylene, which is loaded with a soft magnetic powder or ferrite as the electromagnetic wave absorbing constituent are already available on the market. Yet, such sheets, while having an electromagnetic wave shielding ability, are ineffective for heat dissipation.
Materials endowed with both the ability to conduct heat and the ability to absorb electromagnetic waves have recently been described in the art. For example, JP-A 11-335472 discloses that sheet-like structures fabricated from a matrix material such as silicone gel that contains a ferrite (e.g., Mn—Zn ferrite, Ni—Zn ferrite) have electromagnetic noise suppressing effects. However, because such sheets are loaded with an electromagnetic wave absorbing filler, they are rigid. Moreover, they have a low thermal conductivity and are thus poorly suited for use as heat dissipating articles.
One object of the present invention is to provide electromagnetic wave absorbing heat conductive compositions endowed with both an excellent ability to dissipate heat and outstanding electromagnetic wave absorbing properties which suppress the generation of electromagnetic noise. Another object of the invention is to provide thermosoftening electromagnetic wave absorbing heat dissipating sheets formed from such compositions. An additional object is to provide a method of installing such compositions for the purpose of heat dissipation.

This patent is subject to a terminal disclaimer.

Electromagnetic wave absorbing thermally conductive composition and thermosoftening electromagnetic wave absorbing heat dissipation sheet and method of heat dissipation work


A barrier material deposited as a barrier film layer in a semiconductor device to reduce the interdiffusion of materials of varying electrical conductivity comprising adjacent layers in a semiconductor device is provided. The barrier material contains a transition metal, aluminum, silicon and nitrogen as essential ingredients. Suitable transition metals are tantalum and titanium. The material provides excellent resistance to diffusion across the range of temperatures occurring in an integrated circuit manufacturing process. The material also exhibits good adhesion to materials used in semiconductor processes.

1. Field of the Invention
The invention relates in general to the field of integrated circuit manufacturing technology and, more particularly, to a new material which can be deposited as a layer onto a semiconductor wafer to serve numerous purposes, including acting as an interdiffusion barrier or an adhesion promoter.
2. Description of the Related Art
In the manufacturing of integrated circuits, which are also referred to as semiconductor devices, numerous microelectronic circuits are simultaneously manufactured on semiconductor substrates. These substrates are referred to as wafers. A typical semiconductor wafer is comprised of a number of die. Each die contains at least one microelectronic circuit, which is typically replicated across all of a wafer's dies. One example of a microelectronic circuit which can be fabricated in this way is a dynamic random access memory or "DRAM".
Although referred to as semiconductor devices, integrated circuits are in fact fabricated from and contain numerous materials of varying electrical properties. These include insulators or dielectrics, such as silicon dioxide, and conductors, such as aluminum or tungsten, in addition to semiconductors, such as silicon and germanium. The most common semiconductor employed is silicon.
In state of the art integrated circuits, it is common for the design to require interfaces between layers of varying electrical properties. The interface between the two layers may constitute the entire surface of the die, or the interface may occur when conductive paths or openings are formed to connect or complete different circuits that have been fabricated within a die. One method to complete different circuits is through the use of conductive paths in or on an insulative layer which provide for an interface between a conductive, typically metal, layer and a semiconductive substrate, typically a silicon layer. Conductive paths of this variety are typically referred to as contact openings or contacts. The contact opening allows for an interface between the underlying semiconductive layer and the subsequently deposited conductive layer.
It is common for a design to require an interface between other layers, such as between two different layers of metallic conductors, between an insulator and a metal conductor, between an oxide and a semiconductor, and between two different semiconductors. Interfaces between other layers are also known. Again, these interfaces may constitute the entire surface area of a die or they may be restricted to the narrow recesses of a conductive path formed between the two layers. Conductive paths providing an interface between pairs of layers may be referred to in the art as contacts or contact openings, or they may be referred to as vias or some other term. Because of the inconsistent use of these terms, the term conductive path will be used herein to refer to such openings formed in a semiconductor process to connect layers regardless of which layers are thereby connected.
There are several difficulties inherent to these interfaces. One difficulty is due to the existence of common fabrication steps which require protracted annealing of the devices at elevated temperatures, often in excess of 500.degree. C. These temperatures are especially problematic for interfaces between semiconductor and conductor. At these temperatures the metallic conductor and the semiconductor can rapidly interdiffuse into the adjacent region. The interdiffusion of these materials is driven by the concentration gradients. This leads to a lower energy state of the composite material, which is the preferred stable state. This desire or trend toward a lower energy state is embodied in the Second Law of Thermodynamics which states, in effect, that whenever a spontaneous event takes place in the universe, it is accompanied by an overall increase in the degree of randomness (i.e., an increase in entropy). As a practical consequence of the Second Law of Thermodynamics, matter has a tendency to diffuse from areas of high concentration (i.e., high energy) to low concentration (i.e., low energy); hence, the interdiffusion of conductive and semiconductive layers. The interdiffusion changes the electrical properties of the two regions and in particular the semiconductor region, resulting in an increased likelihood of the production of inoperative devices. The interdiffusion of the two regions can also occur at room temperature, although at a much slower diffusion rate. Interdiffusion between other layers may also occur, increasing the likelihood of producing inoperable devices.
These interdiffusion concerns generally have dictated the need for a barrier material to be deposited at the interface of the two layers when there is sufficient concern over interdiffusion of the two regions. Specifically the barrier material is deposited onto the surface of one layer prior to the deposition of another layer onto the barrier layer. For example, a barrier material can be deposited into a contact opening to prevent the interdiffusion between an underlying semiconductor layer and a subsequently deposited conductor layer. Titanium nitride (TiN) and titanium tungsten (TiW) are typical of the compounds used as barrier materials (i.e., to form a barrier layer). The barrier materials are typically deposited as a thin film or layer over the exposed surface of the die, including any intended interface. The deposited surfaces would include the walls and base of conductive paths. The thickness of these barrier films is typically in the range of 200 .ANG. to 1000 .ANG. although the use of films of other thicknesses is known.
A second difficulty associated with these interfaces is a corollary to the first. Despite interdiffusion concerns, good contact between successive layers of the integrated circuit should be maintained. Therefore, any layer employed as a barrier layer to minimize interdiffusion should exhibit good adhesion qualities to the adjacent layers. Indeed, a thin film may be deposited strictly because of its adhesive properties when the two adjacent layers do not readily adhere to each other. Finally, barrier layers can also be used to tailor the electrical properties of contacts.
One difficulty that limits the widespread use of certain materials as barrier and adhesive layers is their effectiveness at higher temperatures. Although generally effective at room temperature, certain materials may lose their barrier or adhesive properties at the high temperatures to which semiconductors are necessarily exposed. Barrier layers composed of TiN and TiW generally suffer from this limitation. Elevated temperatures are not only common for annealing steps but are often dictated by the limitations of the deposition techniques used to deposit materials onto the semiconductor wafer. Thus, a barrier material which does not exhibit a loss in either its barrier or adhesive properties at elevated temperatures would be extremely useful.
A further complication in integrated circuit manufacturing is the ever increasing trend of reducing the size of the microelectronic circuits. As the size of these circuits, and therefore the size of die regions, decreases, the number of devices produced from any one wafer increases dramatically. However, as the size of these devices decreases, the percentage of reliable circuits produced on any one wafer becomes highly dependent on the ability to deposit films, including films deposited for barrier and adhesive purposes, uniformly across surfaces. These size reductions dictate that barrier materials be deposited at ever decreasing thicknesses, which means that these barriers are even more susceptible to elevated temperatures and the disastrous effects these temperatures can have on interdiffusion. Therefore, one requirement for any new barrier material, deposited as a barrier film or layer, would be that it exhibit greater inherent resistance to thermal energy than those materials previously employed. Additionally, it would be preferred that the adhesion properties of new barrier materials be at least as good as those previously employed. Finally, the trend in size reduction also dictates that new barrier materials must yield deposited films exhibiting greater uniformity in thickness (i.e. they must exhibit improved step coverage) than previous materials. The goal is to avoid the deposition of a barrier film which has holes or gaps within it. If present, these holes or gaps would tend to reduce the barrier properties of the film. As a corollary to this requirement, it would be preferable that any new material used as a barrier or adhesive layer could be deposited by those techniques currently used to deposit thin uniform films. Sputter deposition, chemical vapor deposition, and plasma enhanced chemical vapor deposition are the techniques most commonly employed to deposit the thin films of interest.

Barrier materials for semiconductor devices


A vehicle battery electrical system tester with a hand-held remote control can include a vehicle battery electrical system tester with a radio frequency transceiver and a remote control unit with a radio frequency transceiver. Preferably, the vehicle battery electrical system tester and the remote control unit both include a radio frequency integrated circuit transceiver microchip. In addition, each can include a microcontroller coupled to the transceiver to control the transceiver. Furthermore, each can include an antenna, preferably an integrated circuit antenna. The remote control unit can include a visual display device, such as an LCD display, and an input device, such as a keypad.

Vehicles with internal combustion engines typically include a battery to provide electrical power for starting the engine with an electrical starter motor. When the engine is running, a generator or alternator provides current to recharge the battery for future use. The battery system on a particular vehicle may include a single battery or a pack, that is, multiple batteries connected to each other. In most cases, the battery electrical system on a vehicle operates at an electrical potential difference of 6, 12 or 24 volts.
A variety of vehicle battery electrical system testers have been developed to verify the status of the battery, starting system, charging system and electrical system (collectively, "battery electrical system") on various vehicles. Typically a battery electrical system tester is connected to the positive and negative terminals of a vehicle battery, or to the vehicle electrical and charging system, in order to measure electrical potential and current in the battery electrical system, to diagnose electrical problems with the battery electrical system.
After connecting to the battery electrical system, an operator then performs a sequence of test operations. For example, the operator may initially turn the vehicle electrical system power on, by turning a key or other switch to the "on" position, and then start the vehicle, all the while monitoring the battery electrical system to verify the proper operation of said system.
On some vehicles, particularly large or heavy equipment, the distance between the operator station or control panel of the vehicle from the vehicle battery electrical system connections can be substantial. For example, on heavy equipment, the distance from the battery to the operator station may be forty feet or more. Thus, typically the operator must connect the tester to the battery terminals using test leads or cables that are long enough to reach the operator station of the vehicle; however, long cables can become entangled in the equipment and pose difficulties or danger to the operator. Otherwise, the operator must move back and forth between the location of the battery and the operator station or control panel, which can be time consuming, and in many cases, poses a danger to the operator.
Accordingly, it is desirable to provide a method and apparatus that allows the test operator to monitor and control the tester from a remote location, such as the operator station of the vehicle, without the use of long test leads to connect to the battery electrical system.

Remote control for battery electrical system tester apparatus and method


Foodplant seed for planting in a foodplant field is comprised of a mixture of 97 to 99 parts by volume of a first seed for a foodplant that has been genetically modified to have a resistance to herbicide applied during emergent growth, and 1 to 3 parts by volume of a seed having an included phenotypical difference.

Genetically-controlled foodplants such as herbicide-resistant corn plants and herbicide-resistant soybean plants are well-known and are experiencing increased usage in the United States. Unfortunately, such foodplants cannot be identified by plant characteristics from similar plants that are not resistant to a particular herbicide especially during early stages of plant growth. Persons planning to undertake field weed-control spraying using a particular herbicide are unable by inspection of the growing plants to distinguish fields of a herbicide-resistant foodplant from fields of similar foodplant that is not herbicide-resistant. The application of a weed-controlling herbicide to a field of a foodplant that is not resistant to the herbicide will result in a total field crop loss.
I have discovered that such crop losses may be minimized or eliminated through practice of the present invention. Other objectives and advantages of the present invention will become apparent from consideration of the detailed descriptions and claims which follow.


A method for manufacturing a semiconductor device includes forming a silicon substrate having first and second surfaces, the silicon substrate including no oxide film or an oxide film having a thickness no greater than 100 nm, forming a first oxide film at least on the second surface of the silicon substrate, forming a first film by covering at least the first surface, forming a mask pattern on the first surface by patterning the first film, forming a device separating region on the first surface by using the mask pattern as a mask, forming a gate insulating film on the first surface, forming a gate electrode on the first surface via the gate insulating film, forming a source and a drain one on each side of the gate electrode, and forming a wiring layer on the silicon substrate while maintaining the first oxide film on the second surface.

In producing semiconductor devices, a batch type method, which processes a large number of wafers simultaneously, is an effective method for improving productivity and is widely used.
The current batch type method is commonly performed by using a vertical furnace that performs a film forming process on numerous wafers that are horizontally set and spaced apart from each other in a vertical direction.

Method for manufacturing semiconductor device


A fastener, includes a first clip member having a first base portion and two first arm portions that extend upwardly from two sides of the first base portion, a second clip member locked with the first clip member and having a second base portion and two second arm portions that extend upwardly from two sides of the second base portion, and at least one hook portion extending from a distal end of one of the first and second arm portions, wherein the first and second clip members are arranged horizontally along two different directions, the second base portion is positioned on the first base portion.

Grating panels are often used in forming structural walkways, which requires to be properly positioned in place and secured to a support underneath the grating panels.
FIG. 1 shows a conventional fastener 10 for fixing a grating panel on a support, disclosed in Patent No. KR101467161B1. The fastener 10 includes a clip 100 that has arms 102 respectively extending from four sides of a bottom portion 104. However, since each arm 102 is isolated from adjacent arms of the clip 100, deformation of the clip 100 is likely to occur when a shear load is applied to one arm towards an opposite arm. In addition, the clip 100 is formed based on a cross-shaped piece, which brings problems of material waste or complexity of laying out a plurality of cross-shaped pieces in a large sheet material. The fastener 10 further includes an adapter 106 functioning as a nut element. To keep the adapter 106 within the fastener 10, the diameters of two ends 108 and 110 of the adapter 106 have to be larger than the diameter of a body portion 112, and additional process is required to press the adapter 106 into a through hole 114 of the clip 100. Accordingly, it would be advantageous to have an alternative fastener for fixing the grating panel on the support.


The states or configurations of peer hosts within a host class may be analyzed and enforced by comparing records of the respective systems' states or configurations to one another and taking steps to address any inconsistencies between the records. In such a manner, the respective systems within the host class may identify, analyze and/or correct any changes in states or configurations of any of the systems, which may have been caused by a malfunction or security breach. The configurations may include one or more of a set of data, a version of a software application, a level of permission, a particular operational setting or any other element of operation. The hosts may be defined as peers based on a common location or a common function of each of the systems, or on any other basis, and the records may include any relevant data relating to the states or configurations of each of the systems.

Frequently, a plurality of distributed computer systems (or hosts) may be clustered or grouped together on any basis, such as where each of the systems is in a common location or is dedicated to performing a common function. For example, a number of servers may be clustered to support a particular web site (such as a web site hosted by an online marketplace), in order to ensure the reliability and dependability of any particular functions to be performed by the web site. Additionally, a number of scanning machines or devices may be used to confirm the arrival of large numbers of goods at a warehouse or shipping facility, while a collection of servers may be used to house and control the sending and receipt of electronic mail at an organization's various satellite offices.
Where computer systems are clustered or grouped together for any reason, it is usually very important to ensure that each of the computer systems in the cluster or group is operating in the same state or the same configuration, i.e., to ensure that each of the systems features the same core operating element (such as the same set of data, version of a software application, level of permissions or particular operational setting) as each of its peers. Various problems may ensue if one or more systems of a cluster or group operates in a different state or a different configuration from the other systems in the cluster or group. For example, if some of the hosts in a networked system operate using a different version of a software application (i.e., an older or less advanced version) than others, then the networked system itself is less than fully versatile, and certain instructions or messages may be handled by only a limited number of the hosts in the networked system. Moreover, where a state or configuration of one or more of the hosts in a networked system has changed for any reason (i.e., due to a fault or security breach at one or more of the respective hosts), such a change is difficult to identify or diagnose unless or until a discrepancy in the host's operations is detected through normal operations.
Determining whether a plurality of computer systems is operating in the same state or configuration, and enforcing a common state or configuration among a plurality of computer systems, are usually challenging tasks. Although the configurations of a plurality of systems within a particular fleet or class may be determined and modified as necessary through tooling processes, such processes require defining the state or configuration based on a known, verified master, and comparing each of the respective systems against the master at a predetermined time, in series in a centrally managed manner. Additionally, until the states or configurations of each of the respective systems within a fleet or class is reviewed in such a tooling process and modified or upgraded, as necessary, there is no way to know whether a state or a configuration of one of the respective systems within the fleet or class has changed. Unless tooling processes are persistently run on each of the respective systems, a change in a state or a configuration—which may have occurred due to a fault or security breach, or other potentially serious adverse conditions—may last for an extended period time, unbeknownst to the owners or operators of the plurality of systems.

Peer configuration analysis and enforcement


A vapor-phase growing unit of this invention includes: a reaction container in which a substrate is arranged, a first gas-introducing part having a first gas-introducing tube in which a gas-spouting port opening in the reaction container is formed, the first gas-introducing part serving to supply into the reaction container a first gas consisting of an organic-metal including gas, and a second gas-introducing part having a second gas-introducing tube in which a gas-spouting port opening in the reaction container is formed, the second gas-introducing part serving to supply into the reaction container a second gas which reacts with the organic-metal including gas and whose density is smaller than that of the organic-metal including gas. The gas-spouting port of the first gas-introducing tube and the gas-spouting port of the second gas-introducing tube are arranged along an outside periphery of the substrate arranged in the reaction container.

1. Field of the Invention
This invention relates a vapor-phase growing unit and a method of forming a vapor-phase-growth film, for forming the vapor-phase-growth film on a surface of a tabular or planar substrate such as, for example, a semiconductor wafer by using a plurality of source gases.
2. Description of the Related Art
Various processes are performed on a substrate made of, for example, a semiconductor wafer or the like, in a fabrication of a semiconductor device. For example, a plurality of source gases may be used in a method of forming a vapor-phase-growth film such as, for example, a CVD method and the like.
Particularly, it is possible to form a vapor-phase-growth film of SrTiO3 on a surface of a silicon wafer by a CVD method, in which, for example, an organic-metal including gas that includes strontium (Sr) and titanium (Ti) and oxygen gas are used. This vapor-phase-growth film is useful for example as a capacitor insulating film because of properties thereof.
Generally, formation of a vapor-phase growth film on a wafer by a plurality of source gases is performed usually by using a reaction container in which a plurality of gas-introducing tubes are arranged, placing the wafer in this reaction container, and heating while spouting the source gases form the respective gas-introducing tubes.
Usually, as for a gas-introducing tube in a conventional vapor-phase growing unit, a straight quartz tube having a gas-spouting port formed by a circular through hole at a peripheral wall thereof has been widely known. In addition, another tube having a gas-spouting port formed by a slit-like through hole extending along a circumferential direction thereof has also been known.
In the conventional vapor-phase growing unit, when an organic-metal including gas is used as a source gas, a front-face direction of the gas-spouting port of the gas-introducing tube is set to be oriented toward a center of a wafer so that the source gas is spouted in a direction toward the center of the wafer along a surface of the wafer. Nonetheless, practically, an in-plane ununiformity (ununiformity within the surface) in a vapor-phase-growth film formed on the surface of the wafer is significantly great. After all, there is a problem that it is impossible to form a vapor-phase-growth film having a high uniformity and desired properties.
For example, when an organic-metal including gas that includes strontium (Sr) and Titanium (Ti) and oxygen gas are used, a desired crystal growth cannot be generated on a substrate with a high in-plane uniformity, whereby it is impossible to form the objective vapor-phase-growth film.
Intensive studies on the above problem suggest that it is caused by a significantly great in-plane ununiformity in distribution of the organic-metal including gas on the surface of the wafer.
Specifically, the organic-metal including gas is a gas of high density. Accordingly, when the gas-spouting port of the gas-introducing tube has a circular shape, as for the formed vapor-phase-growth film, a certain degree of the uniformity can be obtained in a small area in a front-face direction of the gas-spouting port (that is to be a direction of a diameter R of the wafer). However, in a lateral direction vertical to the front-face direction, in proportion to the distance from the gas-spouting port, the film thickness is sharply decreased. That is, the state comes to a state of a great ununiformity.
Consequently, a gas-introducing tube whose gas-spouting port is formed by a slit-like through hole extending in a surface-direction of a wafer was used. As a result, the gas spreads in the lateral direction in an area of a small distance from the gas-spouting port. Therefore, as for the formed vapor-phase-growth film, the uniformity of the film thickness was improved in a certain degree in the lateral direction vertical to the front-face direction of the spouting port (that is to be the direction of a diameter R of the wafer). However, in the front-face direction, in proportion to the distance from the gas-spouting port, the film thickness is sharply decreased. After all, it reveals that the state becomes a state of a great ununiformity.

Method for forming a vapor phase growth film


An implementation of a voice-over-Internet protocol (VoIP) system for accomplishing two-way, three-way and conference calling between two or more parties is disclosed, in which new call features are readily adapted. The VoIP system is implemented in a Session Initiation Protocol (SIP) framework in which aspects of Distributed Feature Composition (DFC) architecture are modified and applied to overcome known limitations in the adaptability of existing VoIP frameworks.

The Voice over Internet Protocol (VoIP) community has been developing and improving voice communications systems and applications implemented over the Internet, with the goal of providing, improving upon and expanding call services that are commonly available over public switched telephone networks (PSTNs) alone. Session Initiation Protocol (SIP) is one existing application-layer VoIP for creating, modifying, and terminating call sessions involving one or more users. Such sessions may include Internet telephone dialogs and sessions, multimedia distribution, multimedia conferences, and the like. In existing SIP domains, distributed proxy servers route requests to a user's current location, authenticate and authorize users for various services, implement provider call-routing policies, and provide various call features to users. Call invitation requests are used to create sessions, and carry session descriptions that allow callers and callees to agree on a set of compatible media types for accomplishing multi-party communications. SIP also provides a registration function for a user to subscribe to various call features, such as three-way calling. SIP registration functions also allow users to upload their current locations for use by proxy servers that receive such call requests for a user.
Similar to what has been encountered during the evolution of PSTNs, as new options are added to the suite of available call features in SIP, it becomes increasingly difficult to manage the behavioral complexity of new call features and their resulting interactions with existing call features.
Distributed feature composition (DFC) has been previously developed by certain of the inventors of the present application to contain this feature-interaction problem in PSTN environments. A description of DFC may be found in U.S. Pat. Nos. 6,404,878 and 6,160,883, both of which are assigned to the assignee of the present invention and incorporated herein by reference. DFC allows for the modification and addition of call features while minimizing unexpected call feature interference and system malfunctions. It is a virtual architecture within which a call feature is implemented by a small number of physical components, collectively called a feature box, that are added to a call route by featureless internal calls through the communications network and are connected by known PSTN network mechanisms. A customer call is handled by building a configuration of feature boxes that are dedicated to the appropriate call features assigned to the call in a predetermined order of priority.
Any new desired features are implemented in DFC by as small a number of new components as possible, preferably just one, along with predetermined rules for joining the new components. The architectural style of DFC is similar to dynamic pipe-and-filter technologies, where the feature boxes are like filters, and the internal featureless call connections between feature boxes are like pipes. DFC feature boxes are physically independent entities, each with its own state, sharing no state with other feature boxes and independent of the identities of its neighboring components. DFC feature boxes are also completely dedicated to an assigned call, and only become available to other calls when the assigned call is terminated or cancelled. This independence contributes significantly to the ability of DFC to manage feature interactions, however, requires a large number of physical components to accommodate a large network of users.
DFC architecture may not simply be incorporated into SIP frameworks. First, the systems are implemented in different domain environments having different component types and signaling protocols. The requirements for certain DFC and SIP hardware also conflict in certain areas of implementation. However, it would be beneficial if SIP could be improved to allow for the ready accommodation of new call features therein.
Third party service developments, such as Call Processing Language and SIP Common Gateway Interface, as well as a variety of distributed component architectures and feature interaction protocols, such as Software Engineering Research Library (SERL), Third Party Call Control (3PCC) and Application Server Component (ASC), have been proposed to improve VoIP performance. However, none has definitively addressed the feature interaction problem in SIP.

Telecommunication network system and method in communication services using session initiation protocol


A machine for metering a product into capsules has a number of conveying wheels for conveying the capsules; a metering station for metering the product; an empty-capsule weighing station; and a full-capsule weighing station. The empty-capsule weighing station has a fast-response scale; a first pickup arm for removing a capsule from an empty-capsule conveying wheel and feeding and reclaiming it to and from the fast-response scale; and a second release arm for removing a capsule from the pickup arm and releasing it to the conveying wheel.

Drug metering machines comprise a weighing unit for determining the actual quantity of drug fed into the capsule. The weighing unit comprises first weighing means for weighing the empty capsule, second weighing means for weighing the full capsule, and a central control unit, to which the results of the two weighing operations are transmitted, and which calculates the difference between the two weighing operations to determine the drug quantity by weight actually fed into the capsule. The above weighing means normally have the drawback of being extremely bulky and slow in responding to the weighing operation, with all the obvious consequences in terms of space and output.

Machine for metering a product into capsules


A device, apparatus and a method for containing a liquid within a liquid reservoir using a magnet and applying the liquid to a depression in a plate that is responsive to a magnet are disclosed. In particular there is provided a device for applying a liquid to a depression in a plate that is responsive to a magnet. The plate has a smooth flat surface. The device includes a reservoir for holding the liquid. The reservoir includes a wall which has an inner perimeter, an outer perimeter, a top surface and a bottom surface. The bottom surface of the wall is adapted to closely contact the smooth flat surface of the plate. The device also includes at least one ring magnet adjacent the outer perimeter of the wall of the reservoir.

Apparatus for printing images on substrates, in particular, those which use a plate having depressions filled with ink whereupon the substrate to be printed on is contacted with the plate, are known in the art. Additionally, apparatus for printing images on substrates, in particular, those which use a pad which contacts a plate having depressions filled with ink whereupon the pad prints the image on the substrate, are known in the art. Such transfer printing and pad printing apparatus require a source of the ink which is applied to the plate to fill the depressions in the plate. The apparatus also requires a means for removing ink from the surface of the plate without removing the ink filling the depressions.
Ink cup or reservoir devices which provide both functions are known in the art. The ink cup contains the ink and is held in position over the plate. The ink cup has a generally open bottom which allows ink to contact the surface of the plate including any depressions thereon. The ink cup also has a bottom edge which, when the ink cup is moved along the surface of the plate, acts to remove ink from the surface of the plate while leaving the ink in the depressions in the plate.
The ink cup must be kept in close contact with the surface of the plate and the force around the bottom edge of the ink cup must be even or ink leakage and incomplete removal of ink from the surface of the plate can occur. Providing for contact of the ink cup edge with the surface of the plate by means such as springs (U.S. Pat. Nos. 5,577,442 and 5,476,040) and magnets (U.S. Pat. Nos. 5,392,706, 5,537,921 and 5,003,872) is known. However, even with the use of such means to provide close contact between the ink cup edge and the surface of the plate, leakage or incomplete removal of ink from the surface of the plate can occur.
Accordingly, it would be desirable to provide a transfer printing or pad printing apparatus and a method for transfer printing or pad printing using an ink reservoir device which is held in close contact with the surface of the plate to minimize the occurrence of leakage or incomplete removal of ink from the surface of the plate.


In accordance with an illustrative embodiment of the present invention, an electrical connector assembly to connect the end of a seismic cable to a data acquisition unit includes a body member having a plurality of sockets in one end which react with pins on a companion receptacle. A tubular shell which is rotatably mounted on the body member has threads that make up with threads on the receptacle, and a drive ring which engages a shoulder on the body member to force the sockets onto the pins as thread make-up takes place. As the threads are released, the drive ring moves back into engagement with an opposed shoulder on the body member to positively separate the sockets and pins.

When seismic prospecting is done in shallow bays and marshes having, for example, a water depth of up to about 6 ft., a number of data acquisition units (DAUs) which are floated about 50 meters from one another along a survey line having drop cables suspended therefrom which support and connect hydrophones thereto. Waterproof, multi-channel electrical cables extend between adjacent pairs of the DAUs so that the output signals from the hydrophones are transmitted to a recorder on a boat. The DAUs can be individually anchored to the water bottom in a suitable manner. In response to a source of acoustic energy which is created, for example, by the explosion of a charge of dynamite or an air gun in the water to the side of the survey line, the resulting acoustic waves travel down through the earth and are reflected back upward toward the surface when they encounter a boundary between two earth strata which have substantially different acoustic impedances. The arrival of the reflected acoustic waves is detected by the hydrophones, and is transmitted by the DAUs and the cables to the recorder. The survey results can be used to map the contours of the various underwater geological structures which are under the body of water, and particularly when displayed in multi-dimensional form, such maps provide valuable aids in determining those structures which might contain hydrocarbons in commercial quantities.
After the seismic data has been acquired, it is necessary to retrieve from the water all the equipment including the DAUs, the cable sections, and the hydrophones. To make waterproof connections between the ends of the multi-channel cables and the DAUs, it is a common practice to use connector assemblies that are threaded together in some fashion to achieve a fluid-tight seal. When such assemblies are disconnected by a crew member, serious problems have been encountered due to damage to the pins as the connector members are released. After release of the threads, the pins and sockets are still engaged. To achieve their release, it was common practice to rock the connector member which is located at the end of the cable from side-to-side while pulling thereon. The resultant side loading on the ferrules of the pins, which are molded and bonded in place, produced cracks in the bonds. The next time the cable and its end connections were used, salt water can leak in through these cracks and, in short order, destroyed the electrical integrity of the connector.
A general object of the present invention is to provide a new and improved electrical connector of the type described where the pins and sockets are positively released from one another as the threads which hold the connector members together are released.
Another object of the present invention is to provide a new and improved electrical connector of the type described where a shell that surrounds a body has a threaded portion that is coupled to threads of a companion receptacle and which draw the connector members tightly together to ensure a leak-proof connection.
Another object of the present invention is to provide a new and improved electrical connector assembly of the type described where the unthreading of the shell from the receptacle during disconnection provides a positive separation of the sockets and pins during a substantial portion of the travel of the shell that is necessary to unthread it from the companion threads on the receptacle, whereby release of the sockets from the pins then can be accomplished without applying damaging bending loads thereto.

Positively released seismic cable connector


A workflow, enterprise, and mail-enabled application server and platform supports distributed computing and remote execution of web applications. Lotus Domino online services (DOLS) is used by a web site administrator to configure Internet Notes (iNotes) clients to auto download from server, thus providing iNotes clients with web access using HTTP with various browsers, and with local processing and replication. A local run time model comprises a hierarchy of models including object data store model, security model, indexing model, replication model, agent workflow model and mail model. DOLS provides a layered security model that allows flexibility for controlling access to all or part of an application. The highest level of security is managed through a database access control list (ACL). Further refinements within the security model provide access to specific documents, and their views, forms or folders, and include read access lists, write access lists, form access lists and readers and authors fields.

1. Technical Field of the Invention
This invention pertains to a workflow, enterprise, and mail-enabled web application enhanced for distributed computing and remote execution. More particularly, it pertains to providing a user interface for distinguishing between and manipulate states of replica copies of documents, databases and web sites online and offline.
2. Background Art
Lotus Notes™ is a workflow enterprise and mail enabled application server and platform.
Domino™ is an enhancement to Notes to add web capabilities. Thus, Domino is a workflow enterprise and mail enabled web application server and platform. There is a need in the art to enhance the Domino server and platform to allow distributed computing and remote execution of Domino web applications.
QuickPlace™ is an enhancement to Domino. It is a workflow, enterprise and mail-enabled web application server and environment for rapid creation of collaborative user communities. There is a need in the art to enhance this server and platform to allow distributed computing and remote execution of QuickPlace applications.
Microsoft Exchange™ is a mail enabled application server and platform. This does not support workflow, nor scale easily to an enterprise level. Novel's GroupWise™ is a workflow enabled enterprise server and platform. This does not support mail, nor scale easily to an enterprise level. There is a need in the art for a mail and workflow web application server and environment which supports mail and scales easily and well to the enterprise level, which requires that all software elements need to scale to very large applications with respect to performance, loading, and administration tools.
It is an object of the invention to provide a system and method for enhancing a workflow, enterprise, and mail-enabled application server and platform to support distributed computing and remote execution of web applications.
It is a further object of the invention to provide a system and method for enhancing a workflow, enterprise and mail-enabled web application to allow distributed computing and remote execution of collaborative user community creation.

System and method for developing and administering web applications and services from a workflow, enterprise, and mail-enabled web application server and platform

International Business Machines Corporation


An apparatus relating generally to accumulation is disclosed. In this apparatus, a first subtraction-bypass stage is coupled to receive an input operand and a modulus operand to provide a first difference and the input operand. An accumulation stage is coupled to the first subtraction-bypass stage to receive the first difference and the input operand. The accumulation stage is coupled to receive an offset operand for providing an offset-accumulated result. A second subtraction-bypass stage is coupled to receive the offset operand and the modulus operand to provide a second difference and the offset operand. A consolidation stage is coupled to receive the offset operand, the second difference and the offset-accumulated result to provide a consolidated accumulated result. The first subtraction-bypass stage, the accumulation stage, the second subtraction-bypass stage, and the consolidation stage are for a redundant number system.

In a conventional Direct Digital Synthesizer ("DDS"), there is a phase accumulator ("accumulator") and a sine/cosine lookup table ("lookup table"). Phase accumulation is conventionally implemented modulus 2^N, where N is a width of the accumulator. Because the range 0 to 2^N−1 describes a full circle of phase, simply discarding carry-out information performs a modulus 2^N operation and maps phase angles above 360 degrees back into the range of 0 to 360 degrees.
A conventional DDS may be an N-bit device, where N is large. For example, N may be 48 bits. A large value for N is used to provide precise frequency resolution. However, generally only most significant bits ("MSBs") of the output of such a DDS may be passed to a lookup table, such as in a non-rasterizing DDS for example. By using only the MSBs, and thus truncating the least significant bits ("LSBs"), address size is reduced. In other words, the amount of random access memory ("RAM") may be reduced to control cost.
However, phase noise generate by such truncation can be problematic. Along those lines, to remove such phase noise, exact phase values may be applied to such a lookup table. Unfortunately, heretofore, this meant that either multiple layers of logic were used in an accumulator feedback path or, for an accumulator feedback path to have a latency of greater than one, multiple channels were interlaced.
Accordingly, it would be useful to provide a phase accumulator that overcomes one or more the above-described limitations.


An operator service terminal system connected to a telephone system switch retains the identifications of calling subscribers. Each operator terminal includes memory for storing at least one more subscriber identification than the number of loops served by that terminal. Once an operator services a call, it is not necessary to signal the telephone system switch to identify the caller if the identification is still in memory. In emergency situations, if a call is terminated before a caller can convey the location of the emergency, the calling party identification information can be used to call the caller back or can be relayed to emergency personnel for appropriate action.

This invention relates to telephone operator call processing systems. More particularly, this invention relates to a method and system in which, when a telephone operator receives an emergency call, data regarding the caller is made more readily available.
Many localities are served by emergency response facilities to which residents can direct telephone calls reporting the existence of emergency situations. These emergency response facilities are commonly served by specialized telephone numbers, such as "911" in the United States, or "999" in Great Britain. Such facilities are typically equipped with operator terminals that display the name and location of the calling party, so that even if the caller is unable to complete a message to the emergency operator, the operator has sufficient information to dispatch emergency personnel.
Prior to the introduction of such emergency response facilities, it was common to seek emergency assistance by dialing the local telephone operator--i.e., by dialing "0." As a result, many people, particularly older people or people under the stress of an emergency situation, still tend to dial "0" to reach emergency personnel. In addition, some localities have not implemented a dedicated emergency response number such as "911." Also, if the local telephone company is unable to complete a call to an emergency response center, it may re-route the call to the local operator. Normally, the local operator is able to obtain all of the necessary information from the caller and relay it to the appropriate emergency personnel. However, in this case, if the caller is unable to give all of the necessary information for any reason and the call is terminated before the operator can dispatch emergency personnel, the operator station does not normally retain, or even display, the necessary name and address information referred to above. The local operator must then transmit a special signal to the local telephone switch to which the operator station is connected to retrieve the telephone number of the caller. The operator can then (1) attempt to contact the caller, or (2) relay the information to an emergency response facility as described above, which can use the telephone number to retrieve the name and address and dispatch emergency personnel.
While the necessary telephone number information is stored at the local switch, the ability of a local operator to retrieve that information is dependent on the signaling method in use between the operator station and the local switch, and on the ability of that signaling method to support the request to retrieve the information. And because there can be multiple line instances, or "loops," at the operator station, it is not sufficient to display the last number that called the operator. Rather, the last number for each loop must be available.
For example, in one common configuration, the local switch is one sold under the trademark 5ESS.RTM. by Lucent Technologies, and the operator stations operate under a system known as Operator Service Position System. Different types of signaling may be used between the switch and the operator stations. Under one type of signaling known as Feature Group C with Modified Operator Signaling, the local operator would be able to query the switch to retrieve the information. However, under a newer form of signaling known as Feature Group D, the information could not be retrieved by the operator without redefining the signaling protocol.
It would be desirable to be able to provide a telephone operator terminal system that is able to retain caller identifying information without regard to the type of signaling in effect between the operator terminal and the local telephone switch, and without regard to the number of line instances at the operator terminal.

Method and system for processing emergency service calls


Certain aspects and features include a system and method for monitoring the operational status of assets in an electric power distribution system. For example, an asset monitoring system identifies a zone of operation for an asset under evaluation. The asset monitoring application identifies meters connected to transformers in the zone of operation and obtains meter voltages for the meters over multiple intervals. The asset monitoring application determines a primary voltage for at least one transformer based on at least one meter voltage. The asset monitoring application uses the primary voltage in a power flow calculation to estimate an operational setting for the asset. The asset monitoring application compares the voltages from the power flow analysis using the estimated operational setting and the voltages from the meter voltages across multiple time intervals. Based on the comparison, the asset monitoring application determines an operational status of the asset.

Electricity is delivered through a distribution network that connects a generation system, e.g., a power generator and a transmission system, to end users such as consumers or businesses, using assets such as transformers, distribution lines, and capacitor banks. Due to the complex nature of a distribution system, faults can occur at different places on the system. An example of a fault is a malfunctioning device such as a transformer or capacitor bank. Faults can be caused by external factors, such as when a storm knocks down a power line or by internal factors, such as component failure.
But the existence of a fault is not easily detected. Moreover, the location of a fault within the distribution network is not easily diagnosed. Utility companies may not place measurement devices throughout the network. For example, a lack of power at a customer's premises could be caused anywhere in the distribution network, not necessarily at the end of the line. Household and other equipment is voltage sensitive and therefore can be damaged by over and under-voltages. But over-voltage and under-voltage fault conditions may be more subtle to diagnose and difficult to remedy.
In order to diagnose a fault, a crew of technicians typically travels to the affected areas to check the lines and assets. But because a fault can occur anywhere on the distribution system, and the location of the fault is not easy to diagnose, a technician traces the power line upstream as necessary to find the fault. This is a time-consuming and expensive process.
Other solutions include the placement of hardware monitoring devices at various locations on the distribution network. Such devices include a capability to communicate with a headend system to communicate problems. But given the complexity of the distribution system, such devices are unable to determine whether a problem exists, as more complete analysis that includes the properties of all the assets in the system must be performed. Moreover, placing devices in the field is expensive.
Hence, solutions are needed to more quickly and effectively diagnose the operational status of an electric resource distribution system without the addition of infrastructure in the field.


Auxiliary washing device in a washing machine comprises a beam mounted on an upper side of an outer tub and extended to an inner space of a washing tub, and a washing bar supported at an extended end of the beam to be capable of swinging. The washing bar is swung upwardly by a motor and downwardly by a torsion spring. When electric power to the motor is stopped at the position in which the washing bar is swung upwardly by the motor, the washing bar swings downwardly by the torsion of the torsion bar to strike laundry in the washing tub. Thus, washing is enhanced by the impact to the laundry, and the laundry is stirred upwardly and downwardly. Therefore, inefficiency in the upper part of the washing tub due to the washing operation only by pulsator is prevented, and washing of all clothes is enhanced.

1. Field of the Invention
The present invention relates to an auxiliary washing device in a washing machine, and more particularly to an auxiliary washing device having a washing bar for striking laundry accommodated in a washing tub.
2. Prior Art
Generally, a washing machine which accommodates laundry and performs washing and dehydrating operations has, as shown in FIG. 1, an outer tub 110 installed in a casing 100, a washing tub 120 installed in the outer tub 110 for accommodating laundry and water, a pulsator 130 mounted on a bottom of the washing tub 120 for rotating the washing water in the washing tub 120, a driving motor 130 disposed under the outer tub 110 for driving the pulsator 130, and a gear assembly 150 for transmitting the power of the driving motor 140 selectively to the pulsator 130 and the washing tub 120. In the washing operation, the power of the driving motor 140 is transmitted to the pulsator 130 through the gear assembly 150 in order to rotate the pulsator 130, by which vortical air flow is generated in the washing tub 120. The pulsator 130 may possibly be rotated in bilateral directions according to the operation of the driving motor 140. The washing operation of the laundry accommodated in the washing tub 120 is performed by the vortical water flow generated by the pulsator 130.
In the dehydrating operation, the power of the driving motor 140 is transmitted to both the washing tub 120 and the pulsator 130, so the washing tub 120 is rotated together with the pulsator 130 at a high speed. The dehydrating operation is performed by centrifugal force generated in that situation.
In such a conventional washing machine, strong water flow is generated in the lower area of the washing tub 120, but water flow is weak in the upper area of the washing tub 120 since the pulsator 130 is rotated in the lower part of the washing tub 120. Thus, if the amount of the laundry is great, the washing operation is efficiently performed in the lower part of the washing tub 120, but is not efficiently performed in the upper part of the washing tub 120. Moreover, according to the tendency that the size of a washing machine has become larger, the washing tub 120 of great capacity is adopted, so the laundry is not efficiently washed by the pulsator 130 installed in the bottom of the washing tub 120.


This invention provides an extension comprising a first and second side wall each having an aperture, a back wall extending between the first side wall and the second side wall, a spring-loaded releasable lock positioned adjacent to the apertures of the side walls and two retaining posts attached to the back wall near and below the releasable lock. The releasable lock includes a pair of side pins that are each inserted from the corresponding aperture in the first and second side wall into a hole in an adjustable leg of the workpiece. The extension is slid up and down the adjustable leg when the side pins of the releasable lock are moved out of the holes of the adjustable leg and the releasable lock is retained downwards between the retaining posts of the extension. The method of application of the extension to adjustable legs of workpieces is also described.

1. Field of the Invention
This invention relates to an extension for adjustable legs used in stilts, benches and other similar devices.
2. Description of the Prior Art
A wide variety of devices have been designed for extending or diminishing lengths and heights of apparatus such as stilts and benches. As examples, several patents that have been issued in the past few decades follow:
Woodward et al., U.S. Pat. No. 5,368,126, issued on Nov. 29, 1994, patents an adjustable work platform that can be adjusted vertically and that has foldable leg assemblies. The adjustment of the height of the work platform is done by moving the leg assemblies, versus independent extensions for leg assemblies, upwards or downwards through slideable collars of the work platform and positioning a securing pin within the desired aperture in each leg assembly.
Miyamoto, U.S. Pat No. 4,776,545, issued on Oct. 11, 1988, patents a bisymmetric bench stand with two main legs and a pair of cross-linked flat bars. The top ends of the bench stand can be bolted to any of a series of bolt holes in the main legs. The bottom ends of the bench stand are bolted to the main legs. The middles of the flat bars are screwed together at a series of positions corresponding to the bolt holes on the main legs. Height-adjustable auxiliary legs are attached to the bottom of the main legs.
Masterson, U.S. Pat. No. 4,569,516, registered on Feb. 11, 1986, patents a vertically adjustable leg for stilts that comprises upper and lower complementarily vertically slideably interfitted struts. To permit the length of the assembled struts to be readily varied, a quick-action lock is interposed between the struts.
Presently, heights of stilts and similar workpieces are generally adjusted by using quick-action locks. A channel-shaped tube is usually slid within each adjustable leg of the workpiece. The adjustable leg has several pairs of vertically-spaced, horizontally-aligned holes, with each hole being designed to receive a stop peg. A compression spring is often interposed between the stop pegs within the tube to constantly bias the stop pegs outwardly. Each lock is provided with a finger grip. The finger grips are manually urged together to retract the stop pegs from within the pair of holes of the adjustable leg and, thus, to adjust the height of the workpiece by vertical sliding movement of the channel-shaped tube within the adjustable leg of the workpiece. Although the finger grips are designed to be operated manually, considerable manual force is needed to squeeze the finger grips in order to retract the stop pegs from within the pairs of holes of the adjustable leg.
Due to the exposure of the workpieces to foreign material, such as dust, that are present at construction sites, some parts of the lock tend to bind. Because of such tendency to bind, the stop pegs do not always securely lodge themselves within the pair of holes of the adjustable leg. The loose positioning of the stop pegs within the holes of the adjustable leg may cause sudden opening of the lock and result in the fall of the workman.
A need has arisen for a lightweight channel-shaped extension that serves as a secure and accident-free means for easily, quickly and manually adjusting heights of workpieces.

Extension for adjustable leg and method of using


A projection television is provided comprising at least three image projectors for projecting respective images of different colors onto a holographic projection screen. One of the projectors has a first, shortest optical path disposed in a substantially orthogonal orientation with the holographic projection screen and at least two of the projectors are disposed in adjacent, stepped-relation to one another and have respective optical paths that are (i) selectively defined by the stepped-relation of the projectors; and (ii) converge toward the first optical path in a non-orthogonal orientation so as to define angles of incidence corresponding to a lowest level chromatic aberration of the images by the holographic projection screen. The projection screen is formed by a three dimensional hologram representing a three dimensional array of lenticular elements disposed on a substrate. The screen receives images from the projectors on a first side and displays the images on a second side with controlled light dispersion of all the displayed images.

1. Field of the Invention
This invention relates generally to the field of projection television receivers, and in particular, to projection television receivers having screens providing significantly reduced color shift and/or significantly reduced cabinet depth.
2. Background Information
Color shift is defined as the change in the red/blue or green/blue ratio of a white image formed at the center of a projection screen by projected images from red, green and blue projection tubes, when viewed at different angles in the horizontal plane, by observations made at the peak brightness vertical viewing angle.
The color shift problem is caused by the need for at least three image projectors for respective images of different colors, for example, red, blue and green. A projection screen receives images from the at least three projectors on a first side and displays the images on a second side with controlled light dispersion of all the displayed images. One of the projectors, usually green and usually in the center of an array of projectors, has a first optical path in a substantially orthogonal orientation with the screen. At least two of the projectors, usually red and blue and usually positioned on opposite sides of the central green projector in the array, have respective optical paths converging toward the first optical path in a non orthogonal orientation defining angles of incidence. Color shift results from the non orthogonal relationship of the red and blue projectors, relative to the screen and to the green projector. As a result of the color shift, color tones may differ at every position on the screen. The condition in which the color tone difference is large is often referred to as poor white uniformity. The smaller the color shift, the better the white uniformity.
Color shift is denoted by a scale of numbers, in which lower numbers indicate less color shift and better white uniformity. In accordance with a common procedure, values for the red, green and blue luminance are measured at the screen center from a variety of horizontal viewing angles, typically from at least about xe2x88x9240xc2x0 to +40xc2x0, to as much as about xe2x88x9260xc2x0 to +60xc2x0, in 5xc2x0 or 10xc2x0 increments. The positive and negative angles represent horizontal viewing angles to the right and left of screen center, respectively. These measurements are taken at the peak vertical viewing angle. The red, green and blue data is normalized to unity at 0xc2x0. One or both of the following equations (1) and (11) are evaluated at each angle:                                           C                                      (              Θ              )                                =                      20            ·                                          log                10                                                          (                                                      red                                                              (                      Θ                      )                                                                            blue                                                              (                      Θ                      )                                                                      )                                                    ;                            (        I        )                                          C                                (            Θ            )                          =                  20          ·                                    log              10                                                  (                                                green                                                        (                    Θ                    )                                                                    blue                                                        (                    Θ                    )                                                              )                                                          (        II        )
where xcex8 is any angle within a range horizontal viewing angles, C(xcex8) is the color shift at angle xcex8, red(xcex8) is the red luminance level at angle xcex8, blue(xcex8) is the blue luminance level at angle xcex8 and green(xcex8) is the green luminance level at angle xcex8. The maximum of these values is the color shift of the screen.
In general, color shift-should be no larger than 5, nominally, on any commercially acceptable screen design. Other engineering and design constraints may sometimes require that the color shift be somewhat higher than 5, although such color shift performance is not desirable and usually results in a perceptibly inferior picture with poor white uniformity.
Screens for projection television receivers are generally manufactured by an extrusion process utilizing one or more patterned rollers to shape the surface of a thermoplastic sheet material. The configuration is generally an array of lenticular elements, also referred to as lenticules and lenslets. The lenticular elements may be formed on one or both sides of the same sheet material or on one side only of different sheets which can then be permanently combined. as a laminated unit or otherwise mounted adjacent to one another so as to function as a laminated unit. In many designs, one of the surfaces of the screen is configured as a Fresnel lens to provide light diffusion. Prior art efforts to reduce color shift and improve white uniformity have focused exclusively on two aspects of the screen. One aspect is the shape and disposition of the lenticular elements. The other aspect is the extent to which the screen material, or portions thereof, are doped with light diffusing particles to control light diffusion. These efforts are exemplified by the following patent documents.
In U.S. Pat. Nos. 4,432,010 and 4,536,056, a projection screen includes a light-transmitting lenticular sheet having an input surface and an exit surface. The input surface is characterized by horizontally diffusing lenticular profiles having a ratio of a lenticulated depth Xv to a close-axis-curvature radius R1 (Xv/R1) which is within the range of 0.5 to 1.8. The profiles are elongated along the optical axis and form a spherical input lenticular lenses.
The use of a screen with a double sided lenticular lens is common. Such a screen has cylindrical entrance lenticular elements on an entrance surface of the screen, cylindrical lenticular elements formed on an exit surface of the screen and a light absorbing layer formed at the light non convergent part of the exit surface. The entrance and the exit lenticular elements each have the shape of a circle, ellipse or hyperbola represented by the following equation (III):                               Z                                (            x            )                          =                              C                                      xe2x80x83                                                  x              2                                            1            +                                          [                                  1                  -                                                            (                                              K                        +                        1                                            )                                                                                C                      2                                                                                x                      2                                                                      ]                                            1                2                                                                        (        III        )
wherein C is a main curvature and K is a conic constant.
Alternatively, the lenslets have a curve to which a term with a higher order than 2nd order has been added.
In screens making use of such a double sided lenticular lens, it has been proposed to specify the position relationship between the entrance lens and exit lens, or the lenticular elements forming the lenses. It has been taught, for example in U.S. Pat. No. 4,443,814, to position the entrance lens and exit lens in such a way that the lens surface of one lens is present at the focal point of the other lens. It has also been taught, for example in JP 58-59436, that the eccentricity of the entrance lens be substantially equal to a reciprocal of the refractive index of the material constituting the lenticular lens. It has further been taught, for example in U.S. Pat. No. 4,502,755, to combine two sheets of double-sided lenticular lenses in such a way that the optic axis planes of the respective lenticular lenses are at right angles with respect to one another, and to form such double sided lenticular lenses in such a way that the entrance lens and exit lens at the periphery of one of the lenses are asymmetric with respect to the optic axis. It is also taught, in U.S. Pat. No. 4,953,948, that the position of light convergence only at the valley of an entrance lens should be offset toward the viewing side from the surface of an exit lens so that the tolerance for misalignment of optic axes and the difference in thickness can be made larger or the color shift can be made smaller.
In addition to the various proposals for decreasing the color shift or white non uniformity, other proposals for improving projection screen performance are directed to brightening pictures and ensuring appropriate visual fields in both the horizontal and vertical directions. Such techniques are not of direct interest and are not described in detail. A summary of many such proposals can be found in U.S. Pat. No. 5,196,960, which itself teaches a double sided lenticular lens sheet comprising an entrance lens layer having an entrance lens, and an exit lens layer having an exit lens whose lens surface is formed at the light convergent point of the entrance lens, or in the vicinity thereof, wherein the entrance lens layer and the exit lens layer are each formed of a substantially transparent thermoplastic resin and at least the exit layer contains light diffusing fine particles and wherein a difference exists in the light diffusion properties between the entrance lens layer and the exit lens layer. A plurality of entrance lenses comprise a cylindrical lens. The exit lens is formed of a plurality of exit lens layers, each having a lens surface at the light convergent point of each lens of the entrance lens layer, or in the vicinity thereof. A light absorbing layer is also formed at the light non convergent part of the exit lens layer. This screen design is said to provide sufficient horizontal visual field angle, decreased color shift and a brighter picture, as well as ease of manufacture by extrusion processes.
Despite many years of aggressive developments in projection screen design, the improvements have been incremental, at best. Moreover, there has been no success in surpassing certain benchmarks. The angle of incidence defined by the geometric arrangement of the image projectors, referred to as angle xcex1herein, has generally been limited to the range of greater than 0xc2x0 and less than or equal to about 10xc2x0 or 11xc2x0. The size of the image projectors makes angles of xcex1 close to 0xc2x0 essentially impossible. In the range of the angles of xcex1 less than about 10xc2x0 or 11xc2x0, the best color shift performance which has been achieved is about 5, as determined in accordance with equations (I) and (II). In the range of the angles of a greater than about 10xc2x0 or 11xc2x0, the best color shift performance which has been achieved is not commercially acceptable. In fact, projection television receivers having angles of xcex1 greater than 10xc2x0 or 11xc2x0 are not known.
Small angles of xcex1 have a significant and undesirable consequence, namely the very large cabinet depth needed to house a projection television receiver. The large depth is a direct result of the need to accommodate optical paths having small angles of incidence (xcex1). Techniques for reducing the size of projection television cabinets generally rely on arrangements of mirrors. Such efforts are also ultimately limited by the small range of angles of incidence.
Polaroid Corporation sells a photo polymer designated DMP-128(copyright), which Polaroid Corporation can manufacture as a three dimensional hologram, using proprietary processes. The holographic manufacturing process is described, in part, in U.S. Pat. No. 5,576,853. A three dimensional holographic screen for a projection television was proposed by Polaroid Corporation, as one of many suggestions made during efforts to establish a market for the DMP-128(copyright) photo polymer holographic product. The proposal was based on advantages which Polaroid Corporation expected in terms of higher brightness and resolution, lower manufacturing cost, lower weight, and resistance to the abrasion to which two-piece screens are subjected during shipping. Polaroid Corporation never proposed any particular holographic configuration for the volume holographic elements which might make up such a holographic projection television screen,-and never even considered the problem of color shift in projection television screens of any type, holographic or otherwise.
Overall, despite years of intensive development to provide a projection television receiver having a screen with a color shift less than 5, even significantly less than 5, or having a color shift as low as 5 for angles of xcex1 even greater than 10xc2x0 or 11xc2x0, there have been no advances in solving the color shift problem other than incremental changes in the shapes and positions of lenticular elements and diffusers in conventional projection screens. Moreover, despite suggestions that three dimensional holograms might be useful for projection screens, although for reasons having nothing to do with color shift, there has been no effort to provide projection televisions with three dimensional holographic screens. A long felt need for a projection television receiver having significantly improved color shift performance, which can also be built into a significantly smaller cabinet, has remained unsatisfied.
A projection television receiver in accordance with the inventive arrangements taught herein provides such a significant improvement in color shift performance, measured in orders of magnitude, that a color shift of 2 or less can be achieved with projection television receivers having angles of incidence a in the range of less than 10xc2x0 or 11xc2x0. Moreover, the color shift performance is so significant that commercially acceptable projection television receivers having angles of incidence up to about 30xc2x0 can be provided, in much smaller cabinets. The color shift performance of such large xcex1 angle receivers is at least as good as conventional small xcex1 angle receivers, for example having a color shift of 5, and can be expected to approach or even reach values as low as about 2, as in the small xcex1 angle receivers.
These results are achieved by forsaking the extruded lens screen technology altogether. Instead, a projection television receiver in accordance with an inventive arrangement has a screen formed by a three dimensional hologram formed on a substrate, for example, a polyethylene film, such as Mylar(copyright).
Such a three dimensional holographic screen was originally developed for its expected advantages in terms of higher brightness and resolution, and lower manufacturing cost, lower weight and resistance to abrasion to which two-piece screens are subjected, for example during shipping. The discovery of the color shift performance of the three dimensional holographic screen came about when testing to determine if the optical properties of the three dimensional screen would be at least as good as a conventional screen. The color shift performance of the three dimensional holographic screen, as measured by equations (I) and (II), was so unexpectedly low as to be shocking. The barriers which limited prior art improvements to incremental steps had been eliminated altogether. Moreover, smaller cabinets with projection geometry characterized by larger xcex1 angles of incidence can now be developed.
A projection television having the unexpected properties associated with three dimensional holographic screens, and in accordance with the inventive arrangements taught herein, comprises: at least three image projectors for respective images of different colors; a projection screen formed by a three dimensional hologram disposed on a substrate, the screen receiving images from the projectors on a first side and displaying the images on a second side with controlled light dispersion of all the displayed images; one of the projectors having a first optical path in a substantially orthogonal orientation with the screen and at least two of the projectors having respective optical paths converging toward the first optical path in a non orthogonal orientation defining angles of incidence; and, the three dimensional hologram representing a three dimensional array of lenticular elements having a configuration effective for reducing color shift in the displayed images, the screen having a color shift less than or equal to approximately 5 for all the angles of incidence in a range greater than 0xc2x0 and less than or equal to approximately 30xc2x0, as determined by the maximum value obtained from at least one of the following expressions:                                                         C                                            (                θ                )                                      =                          20              ·                                                log                  10                                                                  (                                                            red                                                                    (                        θ                        )                                                                                blue                                                                    (                        θ                        )                                                                              )                                                              ;                      xe2x80x83                              and                ,                                                      C                                      (              θ              )                                =                      20            ·                                          log                10                                                          (                                                      green                                                              (                      θ                      )                                                                            blue                                                              (                      θ                      )                                                                      )                                                    ,
where xcex8 is any angle within a range horizontal viewing angles, C(xcex8) is the color shift at angle xcex8, red(xcex8) is the red luminance level at angle xcex8, blue(xcex8) is the blue luminance level at angle xcex8 and green(xcex8) is the green luminance level at angle xcex8. The color shift of the screen can be expected to be less than 5, for example, less than or equal to approximately 4, 3 or even 2.
In terms of the known barrier at an angle of incidence of about 10xc2x0 or 11xc2x0, the color shift of the screen is less than or equal to approximately 2 for all the angles of incidence in a first subrange of angles of incidence greater than 0xc2x0 and less than or equal to approximately 10xc2x0; and, the color shift of the screen is less than or equal to approximately 5 for all the angles of incidence in a second subrange of angles of incidence greater than approximately 10xc2x0 and less than or equal to approximately 30xc2x0.
The screen further comprises a light transmissive reinforcing member, for example, of an acrylic material in a layer having a thickness in the range of approximately 2-4 mm. The substrate comprises a highly durable, transparent, water-repellent film, such as a polyethylene terephthalate resin film. The substrate can be a film having a thickness in the range of about 1-10 mils. A thickness of about 7 mils has been found to provide adequate support for the three dimensional hologram. The thickness of the film is not related to performance. The three dimensional hologram has a thickness in the range of not more than approximately 20 microns.
The projection television may further comprise one or more mirrors between the image projectors and the screen. In one preferred embodiment, a projection television is provided comprising at least three image projectors for projecting respective images of different colors onto a holographic projection screen. One of the projectors has a first, shortest optical path disposed in a substantially orthogonal orientation with the holographic projection screen and at least two of the projectors are disposed in adjacent, stepped-relation to one another and have respective optical paths that are (i) selectively defined by the stepped-relation of the projectors, and (ii) converge toward the first optical path in a non-orthogonal orientation so as to define angles of incidence corresponding to a lowest level chromatic aberration of the images by the holographic projection screen. The projection screen is formed by a three dimensional hologram representing a three dimensional array of lenticular elements disposed on a substrate. The screen receives images from the projectors on a first side and displays the images on a second side with controlled light dispersion of all the displayed images.

Projection televisions with three dimensional holographic screens


A bipolar transistor structure includes an intrinsic base layer formed over a collector layer, an emitter formed over the intrinsic base layer, and an extrinsic base layer formed over the intrinsic layer and adjacent the emitter. A ring shaped collector implant structure is formed within an upper portion of the collector layer, wherein the ring shaped collector implant structure is disposed so as to be aligned beneath a perimeter portion of the emitter.

The present invention relates generally to bipolar transistor technology, and, more particularly, to an improved local collector implant structure for heterojunction bipolar transistors (HBT) and method of forming the same.
The improvement in transistor performance, especially the operation speed, is an essential requirement for increased bandwidth and data rate for network communications. As silicon based technology enables large scale integration, an increase in the operation of silicon based devices is a key to achieving a low cost implementation of such systems. The heterojunction bipolar transistor (HBT) is an improvement of the bipolar junction transistor (BJT) that can handle signals of very high frequencies up to several hundred GHz. HBT technology is commonly found in modern ultrafast circuits, such as radio-frequency (RF) systems.
The principal difference between the BJT and HBT is the use of differing semiconductor materials (e.g., silicon, germanium) for the emitter and base regions, thus creating a heterojunction. The effect is to limit the injection of holes into the base region, since the potential barrier in the valance band is so large. Unlike BJT technology, this allows for high doping to be used in the base, thereby reducing the base resistance while maintaining gain.
There are several different critical features in the design of high performance bipolar transistors, including HBT devices. Such features include, for example, the vertical dimension of the transistor, the collector doping, base-collector and base-emitter capacitances, and collector and base resistances. To achieve higher performance, it is generally desirable to reduce the vertical dimension of the transistor, which reduces the transit time and thus can increase performance. Also, it is generally desirable to increase the collector doping concentration. This reduces collector resistance and thus can also increase performance. These goals are generally compatible, as a vertical dimension reduction is achieved partly by the increase in collector doping concentration since the base-collector space-charge region shrinks with higher doping concentrations.
However, simply reducing transistor vertical dimension and increasing the collector doping concentration has the negative result of increasing base-collector capacitance. The increase in base-collector capacitance in turn has a negative impact on the performance of the device, and thus can negate the benefits of reducing the vertical dimension and increasing collector doping concentration. As SiGe HBT switching speeds begin to exceed 350 GHz, it becomes increasingly important to reduce the parasitic base-collector capacitance while also delaying the Kirk effect.
HBT devices usually achieve their peak AC performance at relatively high collector current densities, which are needed to load the parasitic capacitance in a short time frame. As the collector current is increased, a larger portion of the current travels at the perimeter of the emitter due to current crowding. The Kirk effect is due to the high current density, which forces the space charge region of the base-collector junction to get pushed into the collector region, thus reducing the frequency response of the transistor. Accordingly, it would be desirable to construct an HBT device that provides a further reduction in base-collector capacitance, while also delaying the Kirk effect and reducing collector resistance.

Local collector implant structure for heterojunction bipolar transistors and method of forming the same


A nematic liquid crystal composition includes at least one of liquid crystal compounds containing a trans-4-trifluoromethoxycyclohexyl group in a backbone, in which the number of an intramolecular cyclohexane ring is 2 to 4; at least one of compounds in which Δε is less than 1 in absolute value; and at least one selected from liquid crystal compounds containing a naphthalene-2,6-diyl group, a decahydronaphthalene-2,6-diyl group, or a 1,2,3,4-tetrahydronaphthalene-2, 6-diyl group in a backbone, in which Δε is 1 or more in absolute value, and a liquid crystal compound in which the number of a six-membered ring is 2 to 4, and Δε is 1 or more in absolute value.

In a liquid crystal display element such as a twisted nematic, super twisted nematic, or active matrix liquid crystal display element, specifically a medium or small sized liquid crystal display element for a cellular phone, display stability to environmental temperature during use is an essential factor, and liquid crystal materials has been desired with such a low driving voltage that electrical power consumption can be reduced while maintaining responsiveness, with a small frequency dependence of duty driving or a small dependence of an optical property on a driving voltage in a temperature range of −30 to 0° C. or 40 to 80° C. or on a steep driving voltage, and so on.
Specifically, a temperature range of a liquid crystalline phase, which is an absolute value of a difference between a lower temperature limit (T→N) and an upper temperature limit (TN-I) of a liquid crystalline phase, is essential since outdoor use has become common because of the low electrical power consumption of a liquid crystal display element. Also, the demand for a reflective or semi-transmissive liquid crystal display element which does not require a backlight has increased for low electrical power consumption, and a liquid crystal material with a low birefringence has been desired to improve display characteristics.
In the present situation, however, a sufficiently low birefringence value required for a reflective or semi-transmissive liquid crystal display element using a combination of conventional materials has not been achieved, while it is possible to increase the temperature range of a liquid crystalline phase (see Patent Document 1). Therefore, the development of a liquid crystal composition with a sufficiently low birefringence without deteriorating the liquid crystal characteristics such as viscosity or threshold voltage, or the development of the best liquid crystal material for this purpose has been desired.
Meanwhile, a liquid crystal compound containing a trifluoromethoxy group is already known, and several compounds thereof and a liquid crystal composition using these compounds were disclosed (see Patent Documents 2 and 3). These Patent Documents 2 and 3 mention that it is possible for these compounds to be used as a nematic liquid crystal with an excellent co-solubility to liquid crystal compounds or compositions, a low viscosity enabling a quick response, a low threshold voltage enabling low voltage driving, a small birefringence, and a high voltage-holding ratio well enabling active matrix driving. However, Patent Documents 2 and 3 do not mention the specific constitutions for realizing a liquid crystal composition with an extremely small birefringence required for a reflective or semi-transmissive liquid crystal display element while sufficiently maintaining other liquid crystal characteristics.
Also, a liquid crystal composition with a small birefringence using a liquid crystal compound containing a trifluoromethoxy group is already known, and a preferable example thereof was disclosed (see Patent Document 4). However, since a lower temperature limit of a liquid crystalline phase is high, this composition cannot be used as a practical liquid crystal composition.
Therefore, the development of a nematic liquid crystal composition is desired with a small birefringence which is effective in a reflective or semi-transmissive liquid crystal display element and has excellent properties.
Patent Document 1: German Patent Application, Publication-No. 4023107 (see claim 1 on page 2)
Patent Document 2: Japanese Unexamined Patent Application, First Publication No. 2002-53861 (see page 8 to examples)
Patent Document 3: Japanese Unexamined Patent Application, First Publication No. Hei 10-218825 (see page 8 to examples)
Patent Document 4: Published Japanese Translation No. 2002-533526 of PCT (see example 7 on page 32)
An object of the present invention is to provide a nematic liquid crystal composition with a wide temperature range of a liquid crystalline phase, a low threshold voltage, a low viscosity, and a small birefringence. Also, another object of the present invention is to provide a display element using this liquid crystal composition as a constituent member, specifically having excellent quality for a reflective or semi-transmissive liquid crystal display element.