A tennis racquet has a frame which includes a frame head portion with an outwardly facing stringing groove and an inwardly facing surface which is generally convex. The stringing groove includes a pair of angled side wall surfaces. A series of stringing holes extend through each side wall surface and the opposing convex surface to define holes for a pair of generally parallel stringing surfaces. Preferably, the string holes extend at an angle of about 45.degree. relative to the central plane of the stringing area, and the angled surfaces in the stringing groove, and the opposing surface on the convex surface, are parallel to one another and generally perpendicular to the direction of the string hole.

Conventionally, tennis racquets have a head portion defining an opening which contains a plurality of interwoven main (i.e., longitudinal) and cross strings which form a strung hitting surface. The strung surface lies generally in a plane located midway between the front and rear faces of the frame member.
It has been proposed, as an alternative to a single strung surface, to provide two parallel strung surfaces lying generally on opposite sides of the frame, i.e., a double strung racquet. Double strung racquets offer potential advantages over a single strung racquet. However, in practice designing a double strung racquet that would be commercially acceptable poses unique problems. The frame must be strong enough to carry the load of the additional strings, and yet remain at an acceptable weight. Further, the frame must have an acceptable construction in terms of how the strings are secured to the frame.
While there have been a number of previous proposals for double strung racquets, it would be desirable to provide a double strung racquet which, compared to racquets having a single stringing plane, provides two strung surfaces without unduly increasing the weight, which has a frame which provides performance comparable to a single strung racquet, and which has an improved construction, compared to prior proposals for double strung racquets, for securing the strings to the frame.


An addition curable silicone resin composition for a light emitting diode is provided The composition includes an organopolysiloxane that includes a straight-chain segment represented by a formula:—(R12SiO)n—wherein, R1 is an unsaturated aliphatic bonding-free monovalent hydrocarbon group, and n is an integer of 1 or greater, and a resin-like segment consisting of R23SiO1/2 units wherein, R2 is a monovalent hydrocarbon group, an alkoxy group, or a hydroxyl group, SiO2 units, and/or R2SiO3/2 units wherein, R2 is as defined above, in which at least two of all the R2 groups are alkenyl groups. The composition exhibits strong resistance to thermal shock, and is resistant to cracking even under severe temperature cycling.

1. Field of the Invention
The present invention relates to an addition curable silicone resin composition for a light emitting diode (LED), and relates particularly to an addition curable silicone resin material that yields a cured product which exhibits excellent transparency, is ideal for protecting light emitting diode elements, altering or regulating wavelength, or acting as a lens component material, and exhibits favorable crack resistance even under conditions involving high temperature/low temperature cycling.
2. Description of the Prior Art
It is well known that when LEDs are activated and lit, a rapid rise in temperature occurs, subjecting the LED element to a thermal shock. Accordingly, when an LED element is turned on and off repeatedly, the LED element is exposed to severe temperature cycles.
Epoxy resins are generally used as the sealing materials for LED elements. However, because epoxy resins have a high elastic modulus, the bonding wires are subjected to stress and may break as a result of temperature cycling, and cracks may develop within the epoxy resin. Furthermore, as a result of the stress applied by the epoxy resin to the LED chip, there is also a risk of a deterioration in the light emission efficiency caused by destruction of the crystal structure of the semiconductor material. As a countermeasure to these problems, a method that uses a room-temperature curable silicone rubber as a buffer material, wherein the exterior of this rubber is then sealed with an epoxy resin, is now established as an accepted method. However, with this method, because the epoxy resin does not adhere to the silicone rubber, temperature cycling leads to peeling at the interface between the epoxy resin and the silicone rubber, and it is known that the light extraction efficiency deteriorates dramatically over time. The use of silicone resins as alternative materials to epoxy resins has also been proposed (patent references 1, 2 and 3). Because silicone resins exhibit comparatively superior heat resistance, weather resistance and color fastness when compared with epoxy resins, in recent years, LED examples that use silicone resins, primarily with blue LEDs and white LEDs, have become more prevalent. However, although these silicone resins have a lower elastic modulus than epoxy resins, their mechanical properties such as their flexural strength are inferior, meaning they suffer from a tendency for cracks to occur as a result of thermal shock generated during the turning on and off of the LED.
[Patent Reference 1] JP 11-1619 A
[Patent Reference 2] US 2002-0161140 A1
[Patent Reference 3] US 2004-0116640 A1

Addition curable silicon resin composition for light emitting diode


A print head using a thermomechanical actuator is capable of improving ejection efficiency and improving print quality by stabilizing an ejecting direction. In a print head for ejecting droplets with the thermomechanical actuator having a first layer and a second layer, the first layer includes a heat generation layer and the second layer includes a plurality of dielectric layers. The thermomechanical actuator includes a fixed end and a free end. The plurality of dielectric layers are laminated on a droplet ejecting side in relation to the heat generation layer and between the fixed end and the free end at the same film thickness. A linear expansion coefficient of the dielectric layer of the fixed end side is smaller than that of the heat generation layer. A linear expansion coefficient of the dielectric layer of the free end side is larger than that of the heat generation layer.

1. Field of the Invention
The present invention relates to a print head, more particularly, it relates to a print head for ejecting ink with a thermomechanical actuator to perform printing.
2. Description of the Related Art
As an ink ejecting method of a print head used for ink jet printing apparatuses, the following methods are known and utilized: a method for generating bubbles by applying thermal energy to ink; a method for ejecting the ink with an electrical-mechanical actuator constituted by a piezoelectric device; and the like. Additionally, a method using a thermomechanical actuator has been developed in terms of simplicity in processing and high degree of freedom of an ink composition.
Japanese Patent Laid-Open No. 2003-260696 discloses a print head using a thermomechanical actuator constituted of two layers, a heat generation layer and a dielectric layer which constitute a cantilever. The thermomechanical actuator including the heat generation layer and dielectric layer constituting the cantilever will be briefly described with reference to FIGS. 8A to 8C.
FIG. 8A is a top plan view of an ejecting portion of the print head (the top view indicates that the ejecting portion is viewed from the side in which an ink droplet is ejected). FIG. 8B is a cross sectional view taken along line VIIIB-VIIIB of the ejecting portion of the print head shown in FIG. 8A. FIG. 8C is a view for illustrating a state where the ink droplet is ejected from the ejecting portion of the print head shown in FIGS. 8A and 8B.
As shown in FIGS. 8A and 8B, a liquid chamber 2 is formed on a silicon substrate 1, and the ink droplets are ejected from a nozzle 3. A cantilever 4 as the thermomechanical actuator is formed in the liquid chamber 2. The cantilever 4 includes: a heat generation layer 20 which is divided into two heat generating portions by a slit; a conductor layer forming wiring portions 5 (5a, 5b) for supplying power to the two heat generating portions, and a turning electrode 11 for connecting the two heat generating portions to each other; and a dielectric layer 21. The cantilever 4 is formed in a manner that the heat generation layer 20 is first formed, the conductor layer then is laminated on the heat generation layer 20; and lastly the dielectric layer 21 is laminated on the heat generation layer 20 and the conductor layer. A linear expansion coefficient of the dielectric layer 21 is set so as to be smaller than that of the generation heat layer 20. Moreover, the whole cantilever 4 is covered with a thin electrically insulating film (not shown) because of contact with ink. When the two heat generation portions of the cantilever 4 is energized to generate heat, the cantilever 4 is bent upward (toward nozzle 3) due to a difference between the linear expansion coefficients of the heat generation layer 20 and the dielectric layer 21 as shown in FIG. 8C. Thus, ink 7, with which the liquid chamber 2 is filled, is formed into a droplet 8 to be ejected from the nozzle 3.
A cantilever 4 is disclosed in Japanese Patent Laid-Open No. 2004-1517 in which the dielectric layer 21 is sandwiched between the two heat generation layers 20 and 20. First, the upper side heat generation layer 20 is energized so that the cantilever 4 is bent in a direction opposite from the nozzle 3. Next, the lower side heat generation layer 20 is energized so that the cantilever 4 is bent toward the nozzle 3 as shown in FIG. 8C. Thus, the droplets can be ejected by a large driving force.
Additionally, a trapezoid cantilever 4 is disclosed in Japanese Patent Laid-Open No. 2004-82733 in which the width of a fixed end 9 of the cantilever 4 is larger than that of a free end 10 thereof. The large driving force is also obtained by this constitution, and the droplets 8 can be properly ejected.
The ejecting portions of the print heads are arranged zigzag so as to be arranged at high density, as shown FIG. 9. The arrangement allows the nozzles to be arranged at short pitches even if the width of the liquid chamber 2 is increased for ink supply.
Problems of the thermomechanical actuator including the heat generation layers and dielectric layer constituting the cantilever will be described with reference to FIGS. 10A and 10B.
As shown in FIG. 10A, when the cantilever is bent to the maximum, that is, when the free end 10 of the cantilever 4 is brought closest to an inner wall (a roof portion) of the liquid chamber 2, the cantilever 4 is brought into an inclined state from the free end 10 to the fixed end 9. In this state, as indicated by an arrow F in FIG. 10A, a part of the pressure for ejecting the droplets escapes to the fixed end 9, and thus ejection energy cannot be entirely used, and energy efficiency sometimes becomes insufficient.
Additionally, since the cantilever 4 is inclined, the free end 10 of the cantilever 4 does not become parallel with a face 3a (a nozzle face 3a) on which an ejection opening of a nozzle 3 is formed. Accordingly, since an ejection pressure is not applied perpendicularly to the nozzle face 3a, an ejecting direction of the droplet 8 is inclined at the angle θ in relation to a nozzle face vertical line v as shown in FIG. 10A. Thus, a landing point of the droplet 8 ejected from the nozzle 3 may deviate from a target point. When the ejecting portions of the print head are arranged zigzag as shown in FIG. 9, the droplet 8 ejected from the adjacent nozzle 3 of the print head is inclined at the angle −θ in relation to a nozzle face vertical line v as shown in FIG. 10B. That is, if it is assumed that an odd number is assigned to the nozzle shown in FIG. 10A, and that an even number is assigned to the nozzle shown in FIG. 10B, the landing point of the droplet ejected from the nozzle 3 of the odd number may largely deviate from that of the even number.
The present invention was made to solve the above problems. It is an object of the present invention to provide a print head using the thermomechanical actuator, wherein the deviation of the landing point of the droplet ejected from the ejecting portion of the print head is removed even if the ejecting portions of the print head or the nozzles are arranged at a high density. Further, it is an object of the present invention to provide a print head using a thermomechanical actuator which has a high ejection efficiency.

Print head with thermomechanical actuator


Disclosed is a is an improved flood source, and method of making the same, which emits an evenly distributed flow of energy from a gamma emitting radionuclide dispersed throughout the volume of the flood source. The flood source is formed by filling a bottom pan with a mix of epoxy resin with cobalt-57, preferably at 10 to 20 millicuries and then adding a hardener. The pan is secured to a flat, level surface to prevent the pan from warping and to act as a heat sink for removal of heat from the pan during the curing of the resin-hardener mixture.

The present invention relates generally to flood sources used in imaging systems. Specifically, the present invention is an improved flood source, and method of making the same, which emits an evenly distributed flow of energy from a gamma emitting radionuclide dispersed throughout the volume of the flood source.
The use of imaging systems that utilize energy from a gamma emitting radionuclides is a well known and well understood technique. The technique relies in one aspect upon those sources of energy, which are known in the trade as flood sources. Flood sources are typically used for checking the performance of nuclear medicine imaging systems. The size and shape of the flood sources are designed to closely match the size and shape of the gamma camera head. When this flood source is placed in the field of view of a nuclear medicine gamma camera, the flood ideally presents a uniform level of activity that produces a uniform gray image in the camera field-of-view. Defects in the image then appear as lighter or darker regions that indicate the locations of camera detectors that are not properly tuned. Thus, it is highly desirable to have the flood source present as uniform a level of activity as can be achieved.
Several investigators have attempted to solve the problems created by flood sources with less than optimum uniformity. For example, U.S. Pat. No. 4,882,494, issued Nov. 21, 1989 to Rogers, et. al. and entitled xe2x80x9cApparatus and method for flooding a nuclear imaging device with radiation from an imaging sourcexe2x80x9d describes a method for correcting the non-uniformity in count density of nuclear imaging sources and an apparatus for carrying out the method. As described within the patent, the problem arises because standards with a stated certified non-uniformity of xc2x11% may actually have a much higher non-uniformity if standard National Electrical Manufactures Association (xe2x80x9cNEMAxe2x80x9d) procedures are applied, since certified non-uniformity is based on a sampling of counts from the surface of the standard rather than on a total surface radiography. Also, since non-uniformity is quantified from counts in only two smoothed pixels (the maximum and the minimum), the method is potentially dependent on small flaws. Thus, to solve these problems the ""494 patent proposes a method which includes the steps of positioning a nuclear imaging flood source beneath or adjacent a nuclear imaging device such as a gamma camera having a plurality of radiation sensing elements and moving the source in a controlled motion thereby blurring or diminishing the effects of any non-uniformities in the source, (i.e., insuring that each sensor or detector in the camera receives radiation from more than one radiation-emitting area of the source so that each sensor receives a more similar amount of light (radiation) than if the source was not moved). As taught by the ""494 patent, the movement of the source can be accomplished over a long period of time, in a pattern, in a reproducible pattern, continuously, in a complex motion, or repetitively. Clearly, if the problems solved by such a method may be solved instead simply providing a uniform flood source, the type of expensive and elaborate equipment required by schemes such as that taught in the ""494 patent may be eliminated. Thus, there exists a continued need for more uniform flood sources.
Several different designs of flood sources are available from a variety of commercial suppliers, and it may be easily appreciated that the market for flood sources is keenly competitive. As such, one may readily survey the state of the art in flood source design and manufacture simply by viewing the competitive landscape. For example, the Syncor(copyright) Corporation of 6464 Canoga Avenue, Woodlad Hills, Calif. currently distributes a variety of rectangular and circular flood sources made by DuPont that are claimed to have a coefficient of variation of less than one percent (1%) with less than three percent (3%) maximum deviation from the mean, a differential non-uniformity of less than one point eight percent (1.8%), and integral non-uniformity of less than two point five percent (2.5%). The Biodex Medical Systems Corporation of 20 Ramsay Road, Shirley, N.Y. 11967-0702 makes available Co57 flood sources which it advertises as having non-uniformity of less than plus or minus one percent (1%) at two standard deviations. Thus, while the state of the art of flood source manufacture has produced flood sources having high levels of uniformity, there exists a need for improved methods for making flood sources and improved flood sources having even greater levels of Co57 source uniformity.
Accordingly, it is an object of the present invention to provide a flood source that presents a uniform radionuclide source distribution and emits energy having a high level of uniformity across the surface of the flood source.
It is a further object of the invention to provide a flood source placed within a shell having a bottom and sides defining a volume, wherein the flood source is made of a batch consisting of an epoxy resin of CY-507 resin and HY-2963 hardener in a ratio of resin to hardener from 2.5:1 to 3:1, and the epoxy resin is further mixed with a gamma emitting radionuclide having an energy between 90 keV and 375 keV, and at least one colored dye that provides a visual indicator of uniformity of the flood source batch and a cover fitting over the shell.
It is a further object of the invention to provide a flood source wherein the gamma emitting radionuclide is Co57.
It is a further object of the invention to provide a flood source wherein the gamma emitting radionuclide is Co57 and is distributed uniformly throughout the volume of the flood source batch.
It is a further object of the invention to provide a flood source wherein the gamma emitting radionuclide is Co57 emits at least 5 millicuries.
It is a further object of the invention to provide a flood source wherein the gamma emitting radionuclide is provided in the chemical form CoCl2.
It is a further object of the invention to provide a flood source wherein the shell and the cover are fabricated from ABS plastic.
It is a further object of the invention to provide a method of fabricating a flood source having the steps of providing a shell having a bottom and sides defining a volume, preparing a mixture of HY-2963 hardener with a gamma emitting radionuclide having an energy between 90 keV and 375 keV and at least one colored dye that provides a visual indicator of uniformity of the flood source batch, mixing the hardener, radionuclide, and colored dye until the colored dye is uniformly dispersed throughout said hardener, mixing the hardener, radionuclide, and color dye with an epoxy resin of CY-507 resin in a ratio of resin to hardener from 2.5:1 to 3:1 until the colored dye is uniformly dispersed throughout the epoxy resin, placing the mixture of hardener, radionuclide, color dye, and epoxy resin within the volume defined by the shell, allowing the mixture to cure, and sealing the shell with a cover fitting over the shell.
It is a further object of the invention to provide a method of fabricating a flood source wherein the shell is affixed to a level surface when the mixture of hardener, radionuclide, color dye, and epoxy resin is cured to prevent the shell from warping due to the heat of the curing reaction.
It is a further object of the invention to provide a method of fabricating a flood source wherein the shell is affixed to a level surface by means of a heat conductive clamp when the mixture of hardener, radionuclide, color dye, and epoxy resin is cured within the volume defined by the shell to prevent the shell from warping due to the heat of the curing reaction.
It is a further object of the present invention to provide a heat conductive clamp fabricated of aluminum.
It is a further object of the invention to provide a method of fabricating a flood source wherein the mixture of hardener, radionuclide, color dye, and epoxy resin is purged of bubbles prior to curing the mixture within the volume defined by the shell.
These and other objects of the invention are accomplished through the present invention which provides an improved design for flood shells featuring a durable and attractive vacuum-formed ABS plastic outer shell, and a durable and uniform epoxy resin filler of uniform thickness and which contains a uniform distribution of the radionuclide cobalt-57. When this flood source is placed in the field of view of a nuclear medicine gamma camera, the flood presents a uniform level of activity that produces a uniform gray image in the camera field-of-view. Defects in the image appear as lighter or darker regions that indicate the locations of camera detectors that are not properly tuned. Typically, the active volumes of the flood sources are approximately 24-inches round by ⅙ to ⅕-inch thick for a round flood source, or 16xc3x9724-inch by ⅙ to ⅕-inch thick for a rectangular flood source, although the present invention contemplates a wide variety of shapes and sizes for flood sources and the invention should be understood to encompass any flood source manufactured by the method described herein, regardless of its shape or size. The flood sources of the present invention are preferably formed with sturdy handles for carrying and positioning under the camera. Preferably, a lead-shielded shipping case is used to transport and store the flood source when it is not in use. The physical half-life of the cobalt-57 activity in the flood source of the present invention is approximately 271 days (9 months), meaning that the activity within the flood source decreases by one-half every nine months.

Quality assurance flood source and method of making


A method synchronizes a radio communication system that is divided up into radio cells. According to the method, every radio cell has one base station each for the radio coverage of a plurality of mobile stations assigned to the radio cell. The base station receives, in addition to mobile station signals of its own radio cell, mobile station signals of neighboring radio cells. The base station determines, on the basis of the mobile station signals received, the number of mobile stations and compares this number with a defined threshold value. When the number determined falls below the threshold value, a first synchronization method for synchronizing the base station and the assigned mobile stations is used, the first method corresponding to an assigned transmission standard of the radio communication system. When the threshold value is exceeded, a second synchronization method is used for synchronizing the base station and the assigned mobile stations.

The invention relates to a method for synchronizing a radio communication system divided up into radio cells.
In a cellular radio communication system the necessary multiple use of carrier frequencies in adjacent radio cells gives rise to what is termed "co-channel interference". In order to reduce this interference, the available carrier frequencies are assigned to individual carrier frequency sub-resources. Each carrier frequency sub-resource is then permanently allocated in each case to a radio cell with the aid of what is termed a "frequency reuse" planning method in such a way that only minimal co-channel interference is caused in the radio cells taking into account minimum physical distances between the radio cells.
Said fixed allocation of carrier frequencies or their transmission resources is disadvantageous in particular when an inhomogeneously distributed number of subscribers occurs in adjacent radio cells. A base station under consideration in one of the radio cells and having to provide coverage to an increased number of subscribers then has an increased demand for transmission resources. If this then gives rise to a lack of transmission resources, then subscribers in the radio cell under consideration who request a new data transmission are rejected.
Accordingly, with an increase in subscriber numbers increased co-channel interference occurs within the radio communication system, which interference can only be influenced to a limited extent by a specified "frequency-reuse factor" on account of the "frequency reuse" planning.
An increase in transmission resources, which is instigated for example in the case of major organized events by subsequent incorporation of further base stations, is not possible in a straightforward simple manner, due to the increase in co-channel interference. Where necessary, the complex and time-consuming "frequency reuse" planning technique must be applied once again.
The use of what are termed "orthogonal frequency division multiplexing" ("OFDM" for short) transmission technologies is gaining increasing significance in particular for future-generation mobile radio networks of cellular design. OFDM mobile radio networks of said type demand high data rates for services such as video transmissions, for instance, which can be transmitted cost-efficiently with the aid of said OFDM transmission technologies. With this approach, a plurality of what are termed "subcarrier frequencies" are used simultaneously in parallel with one another for transmitting a subscriber data stream. A wideband transmission channel is implemented by a plurality of radio transmission channels having a generally identical bandwidth. An OFDM mobile radio network of said kind is in turn to be embodied dependent on a "frequency reuse" planning method that is to be performed with regard to co-channel interference.
The wideband radio transmission channel is "time-dispersive" and is subject to frequency-selective fading, with the result that typically a complex equalization is required on the receive side. In an OFDM transmission the radio transmission channel is subdivided into a plurality of narrower subchannels, with the result that "flat fading" is experienced on each of the subchannels instead of frequency-selective fading, thereby enabling a very simple, typically "single-tap" equalization.
In the simplest case the same modulation scheme, and hence the same transmission bit rate, is assigned each time to each of these radio transmission channels, the assigned transmission bit rates being specified as a function of interference on the respective radio transmission channels. A higher-level modulation method is used for radio transmission channels with low interference than in radio transmission channels that exhibit higher interference. In this manner transmission can be performed with a required quality of service for each radio transmission channel, taking into account an error rate, for example. In the case of a line transmission in the baseband, an OFDM multi-carrier method of said kind is also known under the designation "discrete multitone transmission", or "DMT" for short.
FIG. 3 shows a cellular OFDM radio communication system according to the related art as a representative instance of all mobile radio systems. Three adjacent radio cells FZ1 to FZ3 each have an assigned base station BTS01 to BTS03. Each individual station of said base stations BTS01 to BTS03 provides coverage to a number of the mobile stations T01 to T012 assigned to the respective radio cell FZ1 to FZ3, with a total of four carrier frequencies f9 to f12 being assigned by a "frequency reuse" planning method to a first base station BTS01 of a first radio cell FZ1, a total of four carrier frequencies f1 to f4 being assigned thereby to a second base station BTS02 of a second radio cell FZ2, and a total of four carrier frequencies f5 to f8 being assigned thereby to a third base station BTS03 of a third radio cell FZ3 exclusively for data transmission.
In a connection direction referred to as the "downlink" DL from the base station to the mobile station, each of the carrier frequencies f1 to f12 has seven timeslots TS1 to TS7 as transmission resources, while in a connection direction referred to as the "uplink" UL from the mobile station to the base station each of the carrier frequencies f1 to f12 has five timeslots TS1 to TS5 as transmission resources. Free, unused timeslots are assigned by way of example to the carrier frequencies f2, f7, and f11 and designated by the letter "F".
FIG. 4 is an overview showing a synchronization situation of the radio cells FZ1 to FZ3 depicted in FIG. 3 that corresponds to the related art.
The individual base stations BTS01 to BTS03 are neither frequency-nor time-synchronized with one another. A base-station-specific carrier frequency deviation Delta01 to Delta03 is plotted vertically in each case for each one of the base stations BTS01 to BTS03. Said carrier frequency deviation Delta01 to Delta03 is due in each of the individual base stations BTS01 to BTS03 to electrical components of the respective base station, for example to base-station-specific local oscillators. As the mobile stations T01 to T012 are synchronized to the respective assignable base station BTS01 to BTS03, the base stations BTS01 to BTS03 and the correspondingly assigned mobile stations T01 to T012 also have the respective carrier frequency deviations Delta01 to Delta03 with respect to one another.

Method for synchronizing a radio communication system that is divided up into radio cells


Methods and circuits for chain ring oscillators having a constant delay time over variations of temperature and variations of semiconductor manufacturing process while requiring low operating voltage only have been disclosed. A system current source includes a constant voltage circuit generating a constant voltage and hence a constant current via a resistance element. Main parts of the constant voltage circuit are an operational amplifier and a bandgap reference circuit. Using a series of current mirrors the constant currents are mirrored to current sources contained in each of n-inverter stages of the chain ring oscillator.

(1) Field of the Invention
This invention relates generally to ring oscillator circuits and relates more particularly to a ring oscillator with almost constant delay time even if the operating voltage drops down.
(2) Description of the Prior Art
Ring oscillators are used for a variety of purposes. Usually ring oscillators are used as an internally generated clocking source, or as a stage in a more complex system such as a voltage controlled oscillator (VCO) or a phase locked loop (PLL). They are often used to issue a refresh command for e.g. DRAM memory devices.
For many applications, e.g. memory circuit design, a circuit having a constant delay is very important.
FIG. 1 prior art shows a circuit diagram of a 5-stage CMOS inverter chain ring oscillator. Normally the number of stages is an odd number (3, 5, 7, or . . . ) with the output of the cascade fed back to the input of the inverter chain. An oscillator provides an output at a specific frequency with no input signal required.
All these five inverter stages IN1 to IN5 have an identical circuit configuration. The first stage IN1 is equipped with a CMOS inverter INV1 comprising a PMOS transistor PI1 and an NMOS transistor NI1. Furthermore a PMOS transistor PN1 and a NMOS transistor NN1 provide a current source for this inverter stage IN1. The other stages IN2 to IN5 are equipped identically.
The output of the last stage IN5 is the input INP1 of the first inverter INV1. This input INP1 is connected to the gates of the CMOS transistors PI1 and NI1. The output OUT1 of the first inverter INV1 is connected to the drain of PMOS transistor PI1, to the drain of NMOS transistor NI1 and the input of the second inverter stage IN2.
The PMOS transistor PI1 has its source connected to the operating voltage VCC via PMOS transistor PN1. The NMOS transistor NI1 has its source connected to VSS voltage via NMOS transistor NN1.
The current I1 from voltage VCC to VSS through PMOS transistor P1, resistor R1 and NMOS transistor N1 follows the equation
            I                                      1        =                  VP        -        VN                    R                                                  1              ,wherein VP is the voltage at the drain of transistor P1 and VN is the voltage at the drain of transistor N1. The current I1 is mirrored to the first inverter stage via the current mirrors P1/PN1 and N1/NN1. Accordingly current I1 is mirrored to the other inverter stages as well. In case the operating voltage VCC drops down, the voltage difference VP-VN becomes very small. Especially in the light of new semiconductor technologies (most fabs moved for the most advanced ICs from 0.18 micron to 0.13 microns) the typical operating voltages used to turn the transistors on and off have been reduced from e.g. 2.5 volts to 1.8 volts, the circuits are becoming more sensitive in case of variations during the manufacturing process or in case of changing temperatures. Even if all devices are within manufacturing specifications PMOS devices have a higher speed than normal if the threshold voltage is lower than normal and vice versa the speed of NMOS devices is lower than normal if their threshold voltage is higher than normal.
This means that in case the threshold voltage of the PMOS or NMOS devices is higher than normal the difference of voltages VP and VN will be smaller. Vice versa the difference of voltages VP and VN will be larger if the threshold voltage of the PMOS or NMOS devices is lower than normal. Furthermore the semiconductor devices and resistor R1 depend in their performance upon changes of temperature. Therefore the current I1 and, by mirroring, the currents through the inverter stages IN1 to IN5 will be not constant but vary dependent upon the temperature and upon manufacturing process variations. Thus the delay time of the prior art ring oscillator will vary upon different temperatures and different manufacturing process parameters, even if these parameters are within specifications and even if the operating voltage VCC is regulated.
Since voltage VP>VN and voltage VP equalsVP=VCC−|VTHP1|,wherein |VTHP1| is the threshold voltage of P1, and voltageVN≅VTHN1,wherein VTHN1 is the threshold voltage of N1, the following equation is valid:VCC=|VTHP1|+VTHN1+I1×R1.Accordingly the ring oscillator shown in FIG. 1 prior art can only work precisely if the voltage difference I1×R1 is much larger than the sum of the threshold voltages |VTHP1|+VTHN1
There are known patents to control the delay time of ring oscillators:
U.S. Pat. No. 6,813,210 to Okamoto et al. teaches a semiconductor memory device including a refresh timer for determining a refresh cycle of self-refresh operation. The refresh timer includes a voltage regulator, a ring oscillator and a counter. The voltage regulator generates a bias voltage having positive temperature characteristics. The ring oscillator varies an oscillation cycle of a pulse signal according to the bias voltage. The counter counts a prescribed number of pulse signals and generates a refresh signal for executing refresh operation. The semiconductor memory device thus varies the refresh cycle according to a temperature change, and executes refresh operation with an appropriate refresh cycle.
U.S. Pat. No. (6,188,293 to Miyagi et al.) discloses a low-power consumption integrated ring oscillator capable of stable operation throughout a wide voltage range without undergoing a large frequency change including a first constant voltage generating circuit having an enhancement mode P-MOS transistor and a depletion mode N-MOS transistor and a second constant voltage generating circuit having a depletion mode N-MOS transistor and an enhancement mode N-MOS transistor. A first constant voltage generated by the first constant voltage circuit is applied to a gate electrode of a P-MOS transistor of transmission gates connected between respective cascaded inverters of the ring oscillator. A second constant voltage generated by the second constant voltage generating circuit is connected to the gate electrode of an N-MOS transistor of the transmission gates. By this construction, current consumption is reduced and battery lifetime can be increased. The boosting circuit for writing and erasing an EEPROM circuit may be formed with the low power ring oscillator.
U.S. Pat. No. (5,898,343 to Morgan) discloses a refresh circuit of a memory device including a ring oscillator with a frequency stabilizing circuit. The frequency stabilizing circuit produces compensated voltage signals in response to changes in supply voltage and temperature to modify the conductances of field-effect transistors of the frequency stabilizing circuit to compensate the conductive path of the discharge current of a capacitor from the ring oscillator in order to stabilize the oscillation frequency.

Low voltage operating ring oscillator with almost constant delay time


Jewelry and methods of making jewelry containing a precious metal-base alloy component in bulk-solidified amorphous phase are provided.

Jewelry is generally used as an ornament on the body or as a decorative item to improve the aesthetics, beauty, and intrinsic worth of an item. As an ornament, jewelry is generally worn on the body, such as earrings, necklaces, bracelets, etc. As a decorative item jewelry has been generally displayed with high-value items, such as artistic pieces. In such cases, jewelry may take the form of a frame or handle. Furthermore, the use of jewelry in personal and functional items, such as cell-phones, watches, glasses, guns and pistols, pens, faucets and plumbing is becoming more common. Such personal items have frequent contact with body parts, such as hands, and are subject to a more intensive "wear and tear" environment than other jewelry items.
Because of their attributed intrinsic worth, jewelry is generally made from precious metals such as gold, platinum, and palladium. Jewelry articles made of solid precious metals are quite common, although clad materials and veneered composites are also used to a certain degree. (Herein, jewelry is defined where the metallic component comprises at least a solid piece of precious metal alloy of more than 0.1 mm thickness. Thin-film surface coatings of precious metals are excluded from the jewelry definition, whereas jewelry comprising "veneer" or clad layers of precious metal alloys is included). Furthermore, jewelry is further enhanced in aesthetics, beauty and intrinsic worth by incorporating gemstones. Generally, it is desired that the content of precious metal in the jewelry alloy is above a minimum weight percentage such as 14 karat or 18 karat. Due to the attributed high worth of jewelry, expectations of the quality of jewelry articles are quite high. Jewelry articles are expected to be unique and exceptional in their design and they are expected to be fabricated and finished to very high standards. Even slight imperfections, subtle to the naked eye, are not generally tolerated.
Accordingly, the fabrication and finishing of jewelry articles is a highly tedious process and several challenges have yet to be satisfactorily resolved. The cast articles of precious metals generally lack the desired precision and need substantial effort in finishing operations. Furthermore, the incorporation of gemstone shows significant problems during casting and subsequent fabrication process in order to secure satisfactory and long-term fixing of gemstones firmly in place.
Jewelry articles are also expected to be durable and sustain long life. However, the common precious metal-based alloys have notoriously poor mechanical properties such as yield strength, hardness, and wear resistance. Furthermore, with the use of jewelry in personal items, such as cell-phones, watches etc, various physical and mechanical properties of precious metals have become more critical for the durability of jewelry products. The demand for high yield strength, hardness, corrosion and erosion resistance, and wear and scratch resistance in such products is so overwhelming for the common precious metal-based alloys that new novel solutions are greatly desired.

Jewelry made of precious a morphous metal and method of making such articles


An approach is provided for extending remote network visibility for push functionality. An application is transmitted, via a push agent, from a first network to a device of a second network, wherein the device is configured to execute the application. The device is remotely controlled using the application.

Information Technology (IT) companies (or departments) that manage their customers' (or organizations') computer systems are constantly challenged with the need to provide timely, secure, and cost-effective support. Remote support provides the means for IT professionals to remotely access and control customers' (or organizations') computer systems. This eliminates the need for these professionals to physically travel on-site to address a problem, thereby minimizing delay in response time.
Traditional remote support approaches possess a number of drawbacks. For example, an Application Service Provider (ASP) hosted approach (also known as Software as a Service, SaaS) requires customers to route all centrally stored or logged data communication through a 3rd party data center, thereby potentially introducing security risks. Also, a server software installation deployment model poses complicated, costly integration issues, particularly when implemented into a large IT infrastructure (e.g., corporate network).
Without the need for pre-installed clients on a system, a local push system can be used by the representatives of a support organization to transfer an application to a remote system attended or unattended and execute the application to establish a session connection back to the representative. Unfortunately, this functionality only provides reach to systems that are visible from within the network that the support representative's computer is connected to, thereby presenting challenges to administer or support systems beyond an enterprising network—especially as the enterprise network grows or spreads to multiple locations. It encompasses many aspects of configuring and maintaining the enterprise system, for example, to distribute a necessary application and create configurations as well as providing unattended support. However, as the enterprise grows and cross one or more untrusted domains, it is impractical for the service administrator to reach each computer. Namely, if no extra means are provided, the reach of the service (e.g., control of remote computers and applications) from the support representative's computer is confined to only those computers to which network traffic is routable; consequently, service capability is limited.
Based on the foregoing, there is a clear need for approaches that enable extension of visibility of service application over network, ease of deployment, while minimizing security risks.

This patent is subject to a terminal disclaimer.

Method and apparatus for extending remote network visibility of the push functionality


This disclosure relates to LINGO-1 polypeptides, LINGO-1 polypeptide/ligand complexes, crystals of LINGO-1 polypeptides, crystals of LINGO-1 polypeptide/ligand complexes, and related methods and software systems.

LINGO-1 (LRR and Ig domain-containing, Nogo Receptor-interacting protein) is a transmembrane coreceptor with p75. The coreceptors, with the ligand binding Nogo-66 receptor (NogoR), make up the Nogo receptor complex, which is commonly located on neurons. Disabling the Nogo receptor complex in which LINGO-1 is located can induce myelin and nerve fiber growth. LINGO-1 has been shown to be active in myelin-making cells known as oligodendrocytes, and inhibition of LINGO-1 has also been shown to induce myelin formation. Thus LINGO-1 signaling is predicted to be a negative regulator of myelin production.

Method for identifying or designing a candidate agent that interacts with LINGO-1 polypeptide using a LINGO-1 three-dimensional structure


A pinball machine which includes a ball engaging mechanism is provided such that when a pinball makes contact with a ball engaging mechanism, which propels the pinball, a player feels an impulse from the button that activates the ball engaging mechanism.

The present invention relates generally to a rolling ball game such as a pinball game, and more particularly to a pinball game having a flipper button which is able to move outward towards the player's fingers in response to the pinball making contact with the flipper or a target. The movement of the flipper button to the player's fingers simulates the impact the player would feel if the flipper button had a direct mechanical connection to the flipper or target.
For years, pinball machines or games have provided a source of leisure time enjoyment for a variety of people. Despite the recent proliferation of computerized video arcades, pinball continues to be recognized as a popular pastime. Pinball games offer the player the ability to manipulate an actual physical object (the ball) as a three-dimensional object as opposed to a character on a two-dimensional screen.
When playing pinball, a player usually sets the ball into play with a spring biased arm or plunger. As the ball strikes various scoring elements, such as post bumpers and slingshot bumpers, the player earns points according to the number of times the ball strikes the bumper and the point value of each bumper. Furthermore, it is common for a pinball game to have certain criteria for a player to attempt to accomplish to earn, for example, a Jackpot, bonus points, free games, and extra pinballs. Examples of the above-mentioned criteria include having the pinball make contact with one or more specific targets or sets of targets. It is common to have visual and audio special effects, such as flashing lights and unusual sounds, to signal that the criteria has been accomplished by the player.
Because the ball rolling or playing surface of the pinball table is gently sloped, the force of gravity constantly urges the ball towards the base of the table. Usually mounted near the base of the table are two flippers that may be electro-mechanically actuated by a player by depressing the buttons located on the side of the machine's cabinet. By correctly timing the actuating of the flippers, the player can cause the flippers to strike the ball and propel it into the playing area to again contact the various scoring elements in order to score further points.
In contrast to the bumpers or other scoring elements, movement of the flippers is within the control of the player. These flippers do not detect ball contact like the bumpers and other scoring elements, however, and no points are scored as a result of contact between the flipper and the ball. The flippers are merely ball propelling devices. The primary purpose of the flipper is to keep the ball in play and prevent it from escaping the playing field by passing through the space located between or around the flippers thereby ending the play of that particular ball. However, a novel flipper mechanism capable of detecting contact with the ball is described in co-pending application Ser. No. 07/392,050, filed Aug. 10, 1989 and in U.S. Pat. No. 4,971,323 whose disclosures are incorporated herein by reference.
When a player plays pinball on a conventional machine as described above, the player is not able to actually feel the ball striking the flipper or a target since the flipper or the target are actually moved by an electro-mechanical device. The lack of feeling sensation of the striking of the flipper or target removes some of the attraction of the device when the ball physically contacts the flipper or target.
Furthermore, lacking the feel of the flipper striking the ball diminishes the player's ability to control the direction of the ball to desired areas of the playing area.
Another disadvantage to such a pinball game is that a player's sight is the only sense in which the player is able to determine when to strike the flipper button. The strength of a player's sight could become the deciding factor in the ability to score well.
Another disadvantage of pinball games is that the only means for a player to determine if a certain criteria of the game has been accomplished is to visually scan the playing surface or the scoring display or to listen for an unusual sound. However, visual scanning or hearing an unusual sound can result in the player losing concentration on the game by losing track of the ball and may result in the drainage of the ball from the playing surface.
In view of the above, it is an objective of this invention to provide a pinball game or machine where a player is imparted a physical stimulus in response to the impact of a projectile, such as a pinball, contacting a projectile sensing mechanism, such as a target or flipper.
It is a further objective of this invention to provide a pinball game or machine where a player is imparted a physical stimulus as part of a special effect produced by the pinball machine to signal to the player the accomplishment of certain criteria of the game.


The present invention provides a method for adaptive diversity combining for Wide Band Code Division Multiple Access (W-CDMA) comprising:                splitting multi-path interference into Iknown and Iunknown components,        precomputing said Iknown interference components,        iteratively estimating channel interference after removing Iknown components of the multi-path interference from the pilot symbols,        using the convergence/divergence of the iteration as an indicator of the channel condition, and

Maximal Ratio Combining (MRC) is a technique used to combine the different multipath components from the fingers of a Rake Receiver in CDMA systems. In ideal conditions, MRC is known to provide better Signal to Interference Ratio (SIR) than Equal Gain Combining (EGC) which is another well understood combining technique.
However, MRC requires estimation of the channel impulse response. When the channel estimates are not reliable, as could happen in severe channel conditions, the performance of MRC degrades. With non-ideal channel estimates the performance of MRC can degrade below that of EGC. This is because EGC does not use any channel estimates for combining the paths and therefore its performance is independent of the channel conditions.
Channel Estimation is done on pilot symbols. In the downlink of W-CDMA, the only source of interference is the multipath interference. The pilot symbols are degraded by multipath interference. The level of degradation will depend on the level of multipath interference. Hence the reliability of the channel estimates too will depend on the level of multipath interference. Therefore for more reliable channel estimates to be obtained, the effect of multipath interference on the pilot symbols has to be removed.
It follows that a better receiver would be the one, which chooses its combining technique based on the channel conditions. The problem of the performance degradation of MRC due to non-ideal channel estimates has not been addressed so far.

Adaptive diversity combining for Wide Band Code Division Multiple Access (W-CDMA) based on iterative channel estimation

Abstract: The instant invention also provides a system and configured computer program product for carrying out the above method.


Various embodiments of the present invention relate to power distribution systems and associated methods. In specific examples, the present invention may be applied to use in a vehicle (e.g., an automobile; a truck; a boat; an airplane; a helicopter; a military vehicle).

An automotive electrical system is a formidable combination of high-current and low-current circuitry. In many cases, relays are required for control purposes. In addition, all circuits must typically be adequately fused (e.g., to protect expensive components and to guard against the danger of fire). In order to facilitate the replacement of fuses and relays, and to simplify interconnection of electrical hardware, many different electric power distribution systems have been tried.
One approach that has been tried is to centralize the mounting of fuses and relays and then route input and output connections from this central location. The first systems built using this approach typically included a great deal of point-to-point wiring. Hand wiring is very costly, and manual wiring operations are typically a source of wiring errors that negatively impact product quality.
Another approach that has been tried has been the construction of customized distribution networks stamped from thin metal sheets. These stampings are shaped so that contact tabs protrude through openings in custom designed plastic shells. Although this approach typically yields a higher quality product, tooling costs can be high for both the plastic shells and the stampings since virtually every automobile model typically requires a unique distribution system. At least some of this uniqueness aspect is driven by the proliferation of fuse and relay packages. A distribution product must typically be able to accommodate the fuse and relay components selected by the automobile manufacturer.
Another approach centered around the use of flexible circuit board technology, or "flex circuits." Flex circuits are constructed by depositing conductive material between two flexible insulating layers. Although the unique distribution requirements of each vehicle model would typically require unique flex circuits for each application, tooling costs are typically much lower than the metal stamping/custom plastic housing approach described previously. One disadvantage of the flex circuit approach is that the conductive layers are typically very thin, and the high current densities often required in vehicle power distribution can lead to overheating and possible eventual failure.
In addition, it is noted that within a vehicle electrical system there is typically a need to pass electrical current between a passenger compartment and an engine compartment. This typically requires circuit(s) to pass through a dash panel (or bulkhead) in some manner, which in turn typically creates a need to seal the junction point(s) to prevent water intrusion into the passenger compartment.
In this regard, one conventional method for accomplishing such passing through the bulkhead utilizes an applied or molded on grommet to pass a wire harness directly through the bulkhead. Another conventional method for accomplishing such passing through the bulkhead utilizes a bulkhead connector, which is a connector that is attached directly to and seals against the bulkhead—in this example half of the connector is in the passenger compartment and the other half is in the engine compartment. It is believed that both of these conventional methods require any circuit protection devices to be located elsewhere in the vehicle. Further, it is believed that neither of these conventional methods provides multiple harness junction capability.
Among those benefits and improvements that have been disclosed, other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying figures. The figures constitute a part of this specification and include illustrative embodiments of the present invention and illustrate various objects and features thereof.

Power distribution systems and associated methods


A laser scanning system suitable for annealing applications is described. The problem of keeping the window (through which the laser shines into the system) clean, even though the laser ejects a considerable amount of debris, has been solved by inserting a moveable shutter close to the window between it and the substrate. The center portion of the shutter is an insert of optical quality quartz that is just large enough to allow the laser beam to pass through unimpeded and undiverted. By moving the beam and the shutter in concert it is ensured that the beam always passes through the insert. Most of the debris ejected by the laser as a side effect of its operation is trapped on the shutter. Relatively little material ends up on the quartz insert but when sufficient has accumulated there, the insert can be replaced at much lower cost than replacing the window. By moving the beam back and forth together with movement of the substrate, the entire area of the film on the substrate may be scanned by the beam. In a second embodiment, the quartz insert is omitted and an open slit left in its place. With this arrangement debris will eventually accumulate on the window but at a greatly reduced rate relative to an unprotected window.

1. Field of the Invention
The invention relates to the general field of laser annealing with particular attention to the problem of shielding the laser system from laser emitted debris.
2. Description of the Prior Art
As part of the manufacture of integrated circuits and similar devices, a need may arise to recrystallize an amorphous layer, either in its entirety or, more likely, in selected areas only. This can conveniently be accomplished by means of a laser beam which can be directed to scan an entire area or may be limited to selected areas as desired. Since no diffusion is involved, recrystallization will take place very rapidly once a sufficiently high temperature has been reached. Excimer lasers, which provide very high energy densities during short duration pulses, are well suited for this because such brief, high energy pulses allow small areas to be rapidly heated to high temperatures with little effect on the immediate surroundings.
One side effect of this high concentration of energy, even though the time be brief, is that the surface being irradiated by the laser beam tends to emit debris in the form of evaporant and/or finely divided particulate matter. This is schematically illustrated in FIG. 1 where laser beam 1 is seen to be directed to shine on layer 3 on substrate 4. As a side effect of the beam's interaction with layer 3 the afore-mentioned debris, shown schematically as arrows 5, is ejected. Some of this debris ends up on the underside of window 2. The latter, which is obviously transparent to the laser radiation being used, is needed either to protect the laser optics directly or, more commonly, because the layer 3 is inside an enclosure that may be evacuated or filled with an inert gas, so window 2 forms part of the top side of such an enclosure.
If the underside of window 2 is unprotected, the accumulation of laser debris on its underside will soon render it unsuitable for its intended purpose because it will become opaque to the laser radiation and/or will lose its optical flatness and smoothness. Thus, a number of approaches to protecting the laser admission window may be found in the prior art. For example, Carter et al. (U.S. Pat No. 4,897,520 January 1990) describe a vacuum scoop that removes the debris as it is generated. This approach is clearly unsuitable for use in a vacuum environment. Offord et al. (U.S. H1637 March 1997) minimize the emission of debris by protecting all surfaces not intended for laser irradiation with a layer of aluminum which reflects the beam away. This method is not suitable for processes in which large areas are required to interact with the laser.
Flint (U.S. Pat No. 4,439,259 March 1984) uses a disposable shield made from epoxy and teaches how to make such a shield, including a proper mount for it, at low cost but with the desired optical quality needed for sensitive laser operations. Ichinowkawa (U.S. Pat No. 5,153,607 October 1992) describes a laser shutter mechanism that is interlocked to close whenever a laser printer is opened, as the laser may have been inadvertently left on.
Takenouchi et al. (U.S. Pat. No. 5,561,081 October 1996) describe the use of a laser for annealing semiconductor layers. They minimize the amount of emitted debris by preheating their films and by using a laser beam that has a rectangular cross-section similar to the beam shown in FIG. 1.
The present invention take a different approach from all of the above and describes a shielding system that is long lasting but nevertheless highly effective.


The invention relates to a donor laminate comprising in order, a substrate, an electronically conductive polymer layer in contact with said substrate, and a metal layer.

Transparent electrically-conductive layers (TCL) of metal oxides such as indium tin oxide (ITO), antimony doped tin oxide, and cadmium stannate (cadmium tin oxide) are commonly used in the manufacture of electrooptical display devices such as liquid crystal display devices (LCDs), electroluminescent display devices, photocells, solid-state image sensors, electrochromic windows and the like.
Devices such as flat panel displays, typically contain a substrate provided with an indium tin oxide (ITO) layer as a transparent electrode. The coating of ITO is carried out by vacuum sputtering methods which involve high substrate temperature conditions up to 250° C., and therefore, glass substrates are generally used. The high cost of the fabrication methods and the low flexibility of such electrodes, due to the brittleness of the inorganic ITO layer as well as the glass substrate, limit the range of potential applications. As a result, there is a growing interest in making all-organic devices, comprising plastic resins as a flexible substrate and organic electroconductive polymer layers as an electrode. Such plastic electronics allow low cost devices with new properties. Flexible plastic substrates can be provided with an electroconductive polymer layer by continuous hopper or roller coating methods (compared to batch process such as sputtering) and the resulting organic electrodes enable the "roll to roll" fabrication of electronic devices which are more flexible, lower cost, and lower weight.
Electronically conductive polymers have recently received attention from various industries because of their electronic conductivity. Although many of these polymers are highly colored and are less suited for TCL applications, some of these electronically conductive polymers, such as substituted or unsubstituted pyrrole-containing polymers (as mentioned in U.S. Pat. Nos. 5,665,498 and 5,674,654), substituted or unsubstituted thiophene-containing polymers (as mentioned in U.S. Pat. Nos. 5,300,575, 5,312,681, 5,354,613, 5,370,981, 5,372,924, 5,391,472, 5,403,467, 5,443,944, 5,575,898, 4,987,042, and 4,731,408) and substituted or unsubstituted aniline-containing polymers (as mentioned in U.S. Pat. Nos. 5,716,550, 5,093,439, and 4,070,189) are transparent and not prohibitively colored, at least when coated in thin layers at moderate coverage. Because of their electronic conductivity these polymers can provide excellent process-surviving, humidity independent antistatic characteristics when coated on plastic substrates used for photographic imaging applications (vide, for example, U.S. Pat. Nos. 6,096,491; 6,124,083; 6,190,846;)
EP-A-440 957 describes a method for preparing polythiophene in an aqueous mixture by oxidative polymerization in the presence of a polyanion as a doping agent. In EP-A-686 662 it has been disclosed that highly conductive layers of polythiophene, coated from an aqueous coating solution, could be made by the addition of a di- or polyhydroxy and/or a carbonic acid, amide or lactam group containing compound in the coating solution of the polythiophene.
Many miniature electronic and optical devices are formed using layers of different materials stacked on each other. These layers are often patterned to produce the devices. Examples of such devices include optical displays in which each pixel is formed in a patterned array, optical waveguide structures for telecommunication devices, and metal-insulator-metal stacks for semiconductor-based devices. A conventional method for making these devices includes forming one or more layers on a receiver substrate and patterning the layers simultaneously or sequentially to form the device. In many cases, multiple deposition and patterning steps are required to prepare the ultimate device structure. For example, the preparation of optical displays may require the separate formation of red, green, and blue pixels. Although some layers may be commonly deposited for each of these types of pixels, at least some layers must be separately formed and often separately patterned. Patterning of the layers is often performed by photolithographic techniques that include, for example, covering a layer with a photoresist, patterning the photoresist using a mask, removing a portion of the photoresist to expose the underlying layer according to the pattern, and then etching the exposed layer.
Coated layers of organic electroconductive polymers can be patterned into electrode arrays using different methods. The known wet-etching microlithography technique is described in WO97/18944 and U.S. Pat. No. 5,976,274 wherein a positive or negative photoresist is applied on top of a coated layer of an organic electroconductive polymer, and after the steps of selectively exposing the photoresist to UV light, developing the photoresist, etching the electroconductive polymer layer and finally stripping the non-developed photoresist, a patterned layer is obtained. In U.S. Pat. No. 5,561,030 a similar method is used to form the pattern except that the pattern is formed in a continuous layer of prepolymer which is not yet conductive and that after washing the mask away the remaining prepolymer is rendered conductive by oxidation. Such methods that involve conventional lithographic techniques are cumbersome as they involve many steps and require the use of hazardous chemicals.
EP-A-615 256 describes a method to produce a pattern of a conductive polymer on a substrate that involves coating and drying a composition containing 3,4-ethylenedioxythiophene monomer, an oxidation agent, and a base; exposing the dried layer to UV radiation through a mask; and then heating. The UV exposed areas of the coating comprise non-conductive polymer and the unexposed areas comprise conductive polymer. The formation of a conductive polymer pattern in accordance with this method does not require the coating and patterning of a separate photoresist layer.
U.S. Pat. No. 6,045,977 describes a process for patterning conductive polyaniline layers containing a photobase generator. UV exposure of such layers produces a base that reduces the conductivity in the exposed areas.
EP-A-1 054 414 describes a method to pattern a conductive polymer layer by printing an electrode pattern onto said conductive polymer layer using a printing solution containing an oxidant selected from the group ClO−, BrO−, MnO4−, Cr2O7−2, S2O8−2, and H2O2. The areas of the conductive layer exposed to the oxidant solution are rendered nonconductive.
Research Disclosure, November 1998, page 1473 (disclosure no. 41548) describes various means to form patterns in a conducting polymer, including photoablation wherein the selected areas are removed from the substrate by laser irradiation. Such photoablation processes are convenient, dry, one-step methods but the generation of debris may require a wet cleaning step and may contaminate the optics and mechanics of the laser device. Prior art methods involving removal of the electroconductive polymer to form the electrode pattern also induce a difference of the optical density between electroconductive and non-conductive areas of the patterned surface.
Methods of patterning organic electroconductive polymer layers by image-wise heating by means of a laser have been disclosed in EP 1 079 397 A1. That method induces about a 10 to 1000 fold decrease in resistivity without substantially ablating or destroying the layer.
The application of electronically conductive polymers in display related devices has been envisioned in the past. European Patent Application EP9910201 describes a light transmissive substrate having a light transmissive conductive polymer coating for use in resistive touch screens. U.S. Pat. No. 5,738,934 describes touch screen cover sheets having a conductive polymer coating.
U.S. Pat. Nos. 5,828,432 and 5,976,284 describe conductive polymer layers employed in liquid crystal display devices. The example conductive layers are highly conductive but typically have transparency of 60% or less.
Use of polythiophene as transparent field spreading layers in displays comprising polymer dispersed liquid crystals has been disclosed in U.S. Pat. Nos. 6,639,637 and 6,707,517. However, the polythiophene layers in these patents are non-conductive in nature.
Use of transparent coating on glass substrates for cathode ray tubes using polythiophene and silicon oxide composites has been disclosed in U.S. Pat. No. 6,404,120. However, the method suggests in-situ polymerization of an ethylenedioxythiohene monomer on glass, baking it at an elevated temperature and subsequent washing with tetra ethyl orthosilicate. Such an involved process may be difficult to practice for roll-to-roll production of a wide flexible plastic substrate.
Use of in-situ polymerized polythiophene and polypyrrole has been proposed in U.S. Pat. Appl. Pub. 2003/0008135 A1 as conductive films, for ITO replacement. As mentioned earlier, such processes are difficult to implement for roll-to-roll production of conductive coatings. In the same patent application, a comparative example was created using a dispersion of poly (3,4 ethylene dioxythiophene)/polystyrene sulfonic acid which resulted in inferior coating properties.
U.S. patent application Ser. No. 10/969,889 filed Oct. 21, 2004 and Ser. No. 11/022,155 filed Dec. 22, 2004 disclose donor laminates for transfer of electronically conductive polymers on to suitable receivers wherein the receivers are components of a device. The transfer is accomplished by the application of heat and/or pressure and can be in the form of a pattern. Although quite effective, the conductivity of the transferred layer is limited by that of the electronically conductive polymer, which is often less than metals such as gold or silver. This can put some limitation to applications of the inventions where much higher conductivity is desired.
Although there is considerable art describing various methods to form and pattern electronically conductive polymers, there are some applications where it may be difficult or impractical to involve any wet processing or cumbersome patterning steps. For example, wet processing during coating and/or patterning may adversely affect integrity, interfacial characteristics, and/or electrical or optical properties of the previously deposited layers. Additionally, the device manufacturer may not have coating facilities to handle large quantity of liquid. It is conceivable that many potentially advantageous device constructions, designs, layouts, and materials are impractical because of the limitations of conventional wet coating and patterning. There is a need for new methods of forming these devices with a reduced number of processing steps, particularly wet processing steps. In at least some instances, this may allow for the construction of devices with more reliability and more complexity.
Use of thermal transfer elements and thermal transfer methods for forming multicomponent devices have been proposed previously. For example, Wolk et al. in a series of patents (e.g., U.S. Pat. Nos. 6,114,088; 6,140,009; 6,214,520; 6,221,553; 6,582,876; 6,586,153) disclose thermal transfer elements and methods, for multilayer devices. However, such elements are non-transparent, often including a light-to-heat conversion layer, interlayer, release layer and the like. Construction of such multilayered elements are complex, involved and prone to defects that can get incorporated into the final device. Ellis et al. (U.S. Pat. No. 5,171,650) and Blanchet-Fincher (U.S. Pat. Appl. Pub. 2004/0065970 A1) describe ablative laser thermal transfer of conductive layers. However, such methods are prone to creating dirt and debris that may not be tolerated for many display applications.
It is clear from the prior art that a method to rapidly, cleanly, precisely dry deposit highly conductive materials in continuous or pattern form is needed. Embodiments of the present invention provide such advantages.

Metal and electronically conductive polymer transfer


A method, computer system, and a computer program product for blockchain enabled crowdsourcing is provided. The present invention may include receiving an asset from a content provider. The present invention may also include deploying a smart contract based on the received asset, wherein the deployed smart contract includes a plurality of compensation rules. The present invention then may include partitioning the received asset into a plurality of fragments based on the deployed smart contract. The present invention may further include releasing the partitioned plurality of fragments into a blockchain network. The present invention may also include tracking each fragment within the released plurality of fragments using the smart contract.

The present invention relates generally to the field of computing, and more particularly to crowdsourcing.
The United States has provided protection for individuals with disabilities by enacting the 21st Century Communications and Video Accessibility Act (CVAA) through the Federal Communications Commission. The CVAA updated previous accessibility laws by ensuring newer technologies are accessible to individuals with disabilities. New technologies may include communications access and video programming through updated broadband services, digital innovation and mobile innovation. Audio and video closed captioning and scene descriptions may require a large amount of resources to fulfill the vast content required by the updated technology for the advanced communication services.

INTERNATIONAL BUSINESS MACHINES CORPORATION


A plastic bag includes a front wall and a rear wall that are joined together to define a containment portion. To facilitate pouring a pourable substance from the containment portion, the plastic bag includes a pour spout. The pour spout includes an aperture that is defined in a lip. The lip can be formed into a channel such that the pourable substance is directed through the aperture. The plastic bag also includes a series of ribs that are formed in the region where the bag is folded to define a bottom end. The ribs reinforce the bottom end without compromising the flexibility of the bottom end.

Plastic bags are used for many purposes, including transporting and storing pourable substances. In many applications, reclosable bags are preferred because they can be closed to seal pourable substances or other contents within, and subsequently repeatedly opened and closed as desired. Typically, the plastic bags are made reclosable by means of a matingly engageable zipper-like releasably locking closure.
The general principles for making plastic bags are fairly well-known and are typified in numerous prior patents. A method of manufacturing the plastic bags includes extruding molten material through an annular opening of a die assembly to produce a tubular film that is later flattened, sealed, and cut into individual bags. The annular opening of the die assembly typically includes profile openings to provide male and female profiles that are integral to the tubular film. However, the profile openings make the annular opening asymmetrical. Material moves more easily through the regions of the annular opening near the profile openings to the detriment of the regions of the annular opening that are distanced from the profile openings. The impact is greatest at the region of the annular opening through which the tubular film that forms the bottom end of the bag is extruded. Accordingly, the bottom end of the bag can have a thickness that is unintentionally thinned and that can easily break or crack, particularly under extreme temperature conditions. Simply thickening the unintentionally thinned portion by widening the annular opening in the affected region is a potential, although flawed, solution to this problem since increasing the thickness of the tubular film in the affected region can make the tubular film difficult to flatten, fold, or otherwise handle during the process of forming individual bags. In general, it is desirable to control the characteristics of the tubular film, such as thickness, rigidity, and flexibility, without wasting material or negatively impacting the performance of the tubular film.
Another problem with existing plastic bags is that it is difficult to pour a liquid or other pourable substance from the bags. For example, the user may bend a lip of a plastic bag into a V-shaped channel through which the pourable substance can be directed. However, the flimsiness of the film and the length of the cantilevered lip results in the channel collapsing or flexing under the weight of the pourable substance. Thus, the channel formed by the lip is not suitable to control the direction of flow of the pourable substance from the bag.
Therefore, a heretofore unaddressed need exists in the industry to address the aforementioned deficiencies and inadequacies. What is needed is a plastic bag that is less susceptible to cracking and breaking and that has an improved pour feature.

Plastic bag with pour spout and reinforced bottom end


The invention relates to a fixing mechanism for a tool for treatment of a material, such as machining. The fixing mechanism comprises a combination of a tool (1), its frame (2) and tool holder (3) in the frame of a machine tool. At least one of the connecting surfaces (r, 7) in the tool frame (2) and in the tool holder (3) in the frame of the machining tool, extending mainly in the mounting direction, is shaped as a curved surface. The first contact surface (6) in connection with the tool frame (2) and the second contact surface (8) in the tool holder (3) are adjusted substantially in a direction perpendicular to the mounting direction, to be placed against each other in the operational position of the fixing mechanism, in order to transmit machining force between the tool frame (2) and the tool holder (3).

According to prior art, it is common to use a so-called conic fit, i.e. a Morse conic fit, for fixing a tool, whereby the tool frame and the tool holder are joined to each other by a fixing movement in their axial direction, the release being effected in a corresponding manner in the axial direction. In particular, the conic fit has the disadvantage that the connecting surfaces very easily tend to be clamped too much against each other, particularly under effect of axial forces. For this reason, many systems presently in use comprise special release mechanisms for releasing clamped conic surfaces in connection with the exchange of a tool. As a natural result, the costs of fixing mechanisms required by tool settings are increased, also, the mechanisms are relatively complex and therefore subject to disturbances during the actual machining operation and particularly during the exchange of a tool.

Tool coupling with means for centering and clamping


A suspension device has longitudinal force compliance steer properties to steer a rear wheel to toe-in or toe-out according to increase in longitudinal force applied to wheel treads of a rear wheel. The suspension device includes: a hub bearing housing; suspension links having both edges pivotally attached to a vehicle body and a hub bearing respectively, to support the hub bearing housing; a suspension spring generating reaction force corresponding to relative displacement amount in the longitudinal direction of the hub bearing housing as to the vehicle body; a damper generating damping force corresponding to relative speed in the longitudinal direction of the hub bearing housing as to the vehicle body; and a toe change generating unit generating toe change in a direction where toe change due to longitudinal force compliance properties is temporarily cancelled out or suppressed at an early stage of turning of the vehicle.

1. Technical Field
The present invention relates to a suspension device for vehicle rear wheels, and particularly relates to a suspension device for vehicle rear wheels configured to enable influence of longitudinal force compliance steer generated at an early stage of turning to be suppressed or cancelled out.
2. Related Art
A suspension device for rear wheels of a vehicle such as a vehicle or the like is configured to support hub bearing housings configured to turnably support a rear wheel, via a suspension link (link) pivotally attached to the vehicle body so as to able to stroke in the longitudinal direction.
Such a suspension device for rear wheels preforms, as an example, positioning in the camber directions of the rear wheels using longitudinal pairs of lateral links, and also performing positioning in the toe directions by disposing the pair of lower side lateral links in a manner separated forward and backward.
An example of such a suspension device for rear wheels is disclosed in Japanese Unexamined Patent Application Publication (JP-A) No. 2011-57021. This suspension device performs positioning of the hub bearing housings using front and rear lateral links (lower links) and trailing links pivotally attached to a sub frame to be attached to a rear underfloor of a vehicle body.
One or both end portions of each of these links are connected to the vehicle body or hub bearing housing via a rubber bush for vibration proofing. For example, in the case of lateral force being applied to a vehicle at the time of turning of the vehicle, there is generated lateral force compliance steer in which the toe angle of a rear wheel is changed to either of the toe-in and toe-out directions due to deformation amount difference between the rubber bushes of the front and rear lateral links.
In general, it is desirable that, at the time of turning of a vehicle, the turning outer wheel side has a tendency to toe in, and the turning inner wheel side has a tendency to toe out, and accordingly, rigidities of the rubber bushes of the front and rear lateral links are frequently set such that displacement amount as to lateral force is greater at the front side than at the rear side.
Also, the geometric layout (geometry) of the links making up the suspension may frequently apply bump steer properties such that the turning outer wheel side, that is, bump side (compressed side) has a tendency to toe in, and the turning inner wheel side, that is, the rebound side (expanded side) has a tendency to toe out.
However, in the case of a suspension exhibiting lateral force compliance steer such that, at an early stage of turning, according to lateral force at the time of turning as described above, the outer wheel side toes in, and the inner wheel side toes out, there may be exhibited a tendency in which, according to compliance steer (longitudinal force compliance steer) due to longitudinal force, the outer wheel side toes out, and the inner wheel side toes in.
Thereafter, upon lateral force increasing, and also a suspension stroke starting to generate lateral force compliance steer and bump steer, finally the outer wheel side has a tendency to toe in, and the inner wheel side has a tendency to toe out, but steering stability is deteriorated by the rear wheels being steered to the inverse phase temporarily at an early stage of turning.


An arrangement for the centralized supply of several friction points with an oil/air mixture, wherein several lubricant distributors are arranged in a row one behind the other in a bore of a housing having lubricant ducts and wherein the lubricant distributors are sealed from each other at least at the outside by sealing members against a transfer of the oil/air mixture. The lubricant distributors are combined and connected to form a column-like structural unit. Hollow screws are provided which hold the lubricant distributors together to maintain the column-like structural unit, wherein the hollow screws have throughopenings for the oil/air mixture which are in alignment with throughopenings of the lubricant distributors. In addition, a device is provided for introducing the structural unit into the bore of the housing and for moving the structural unit out of the bore of the housing.

1. Field of the Invention
The present invention relates to an arrangement for the centralized supply of several friction points with an oil/air mixture, wherein several lubricant distributors are arranged in a row one behind the other in a bore of a housing having lubricant ducts and wherein the lubricant distributors are sealed from each other at least at the outside by means of sealing members against a transfer of the oil/air mixture.
2. Description of the Related Art
The arrangement mentioned above is intended especially for the centralized supply of the lubricating points of roll stands or wire trains. In such devices, several friction points, for example, the bearings and sealing members of the individual rolls in the case of a rolling train, are arranged spaced apart from each other and are to be supplied with lubricant. In the past, individual lines were provided from a central oil/air mixer to the friction points of the rolls. This was structurally cumbersome and also difficult to assemble. Most importantly, these supply lines had to be disassembled when the rolls had to be exchanged.
In order to avoid these disadvantages, it is also known in the art to arrange several lubricant distributors one behind the other in a bore of a housing, wherein the housing is part of a frame or the like containing the friction points, for example, the frame of a roll stand. Appropriate lubricant ducts which serve to conduct an oil/mixture to the bearing points and sealing members are provided in the housing. Such an oil/air mixture is composed of air in which oil is finely distributed.
The operation of the arrangement described above is satisfactory. However, the known arrangement has the disadvantage that the assembly and disassembly is complicated. The individual lubricant distributors must successively be introduced into the bore and, in case a repair is required, must successively be removed individually from the bore. This is cumbersome. In addition, there is the danger that, when the respective operating person is not careful, the prescribed sequence of the lubricant distributors is not adhered to during the assembly, i.e., when the lubricant distributors are introduced into the bore. An additional effort is required during the assembly to insert the sealing rings to be provided between the individual lubricant distributors and to ensure that these sealing rings assume the required position in which they provide a problem-free sealing action and that they are not damaged when they are moved past bores.

Arrangement for the centralized supply of several friction points with an oil/air mixture


A disk drive includes a head and a disk, spiral patterns are located on the disk, and the disk drive self-writes servo patterns on the disk using the spiral patterns as a reference for servoing the head. In an embodiment, the disk drive uses preliminary servo patterns to determine repeatable runout of the spiral patterns. In another embodiment, the disk drive reads each spiral pattern with multiple timing windows.

In many processing and computing systems, magnetic data storage devices such as disk drives are used for storing data. A typical disk drive includes a spindle motor for rotating one or more data storage disks having data storage surfaces, a head arm that supports one or more transducer heads, and an actuator for moving the heads radially across the disks to enable the heads to read from and write to concentric tracks on the disks.
In general, the head is positioned very close to the corresponding disk surface. Typical clearance between the head and a smooth disk surface is about one microinch, or less. The close proximity of the head to the disk allows recording very high density servo patterns (embedded servo information) and user data on the disk.
The servo patterns are typically written into servo sectors with uniform circumferential (angular) spacing, and data sectors or blocks are interleaved between the servo sectors. The servo patterns are also arranged in radially extending servo spokes that are interspersed at regular intervals between user data areas on the disk. In addition, the servo patterns are radially close enough to allow servoing at an arbitrary radial position. At a given radius, the servo patterns include coarse identifiers and fine identifiers. The coarse identifiers provide radius and timing information when the head presents a read signal with sufficient amplitude to detect digital data. The fine identifiers are circumferentially sequential, radially staggered, single frequency bursts that provide radial position information when the head is offset from a track centerline enough to present a read signal with partial amplitude.
The servo patterns provide the disk drive with head position information to control the actuator to move the head from starting tracks to destination tracks during random access track seeking operations. Further, the servo patterns provide the disk drive with head position information to control the actuator to position and maintain the head in proper alignment with a track during track following operations when user data is read from or written to data sectors in concentric tracks on the disk surface.
In a standard manufacturing process, a head-disk assembly (HDA) of the disk drive is assembled in a clean room and then transported to a specialized servo writer where the HDA is mounted on a stabilized metrological measurement system. Then, in a time consuming process, the servo writer uses the head to write the servo patterns to the disk. The drive electronics are then assembled to the HDA and the disk drive is moved to a self-scan station where the disk drive is tested for reliable servo operation. Block errors, defects, control tracks and other information are written to the disks at this station. If the disk drive fails the self-scan tests, it is either reworked or scrapped at this late manufacturing stage.
Servo writers write the servo patterns with various processes. For example, a skip-track process writes the servo patterns at every other radius and then writes intermediate servo bursts at every skipped radius. As another example, a sync-skip process writes reference servo patterns at every other radius and then writes final servo patterns at every radius. The sync-skip process avoids the time-consuming step of measuring and compensating for head reader-to-writer offsets.
Disk drives have been developed that self-servo write the servo patterns without a servo writer. For example, an incremental two-pass self-servo write process begins with a first pass that writes reference servo patterns at a position determined by a crash-stop (the mechanical limit of the head's movement) and then servos on the reference servo patterns and writes the next set of reference servo patterns. The first pass repeats as the head moves radially across the disk, with each step servoing on the previously written reference servo patterns to write the next reference servo patterns at the next radial position. During the first pass, the servo loop has no absolute reference to ensure placement of the reference servo patterns at the appropriate radius. After the first pass finishes the complete stroke, a second pass writes the final servo patterns using the reference servo patterns to find the appropriate positions. However, the second pass substantially increases the self-servo writing time.
There is, therefore, a need for improved disk drive self-servo writing which reduces servo writer time, reduces self-servo writing time, improves performance and is simple to implement.

Method of self-servo writing in a disk drive using a spiral pattern


A multi-functional float board structure uses a wedge shape design and is constructed with buoyant materials. The float board includes an the inclined surface design on one side of the float board which when placed on a level surface can facilitate foot stretching for a user prior to any aquatic activities. Furthermore, massage nodes on the inclined surface serve as a sole massage device when a user steps on the incline surface.

Float boards as a swimming aid, facilitate swimmers in aquatic practices such as floating and kicking based on its buoyant nature. Most prior art float boards with a known flat panel design does not provide additional functionality, besides variation in shapes, colors and materials. Any new product development based on existing structure will not be able to create new competitive products while simultaneously satisfying the multilateral requirements of consumers.
To cope with the single-function, lack of innovation and competition deficiencies of the prior art float board design, the industry needs to invent a multi-functional, practical and innovative new structure.


A megasonic liquid stream semiconductor wafer cleaning apparatus and method uniformly removes debris from all points on the surface of a semiconductor wafer. The wafer is rotated about a proscribed axis while the means for producing focused megasonic waves and a liquid stream of cleaning fluid is focused on the wafer so as to apply sufficient energy to clean the wafer yet not cause damage to the electronic circuity embedded in the wafer. A method is provided for moving the outlet port providing the stream of megasonic cleaning fluid across the wafer so that the amount of energy applied to any area of the wafer is relatively constant.

1. Field of the Invention
The present invention generally relates to semiconductor cleaning apparatus, and more particularly, to a megasonic liquid stream cleaning apparatus for cleaning metal wiring patterns.
2. Discussion of the Related Art
During the manufacture of semiconductor devices there are many stages that require cleaning of a silicon wafer or other microelectric workpiece. This is especially true during what is known as back end of the line processing where the interconnect wiring for the circuits are fabricated. It is important to remove any metal debris created by fabrication or testing steps since metal debris can lead to shorts which will cause yield or reliability problems.
One method for cleaning microelectronic wafers is to use a high pressure vertically directed water liquid stream incident on a rotating wafer below. The wafer is disposed in a plane which is at right angles to the incident liquid stream. The nozzle of the liquid stream is attached to a reciprocating arm so that the entire wafer can be accessed. Often, the high pressure within the water column causes damage to metal patterns on the wafers, particularly when thin metal wiring is subjected to the liquid stream. A mathematical analysis of the forces exerted by the conventional spin-clean device indicates very large horizontal forces in the region of the boundary layer of the liquid stream. These forces are at times strong enough to destroy the metallurgy since typical circuit lines are vulnerable to shear forces.
Another spin-clean device operates at a significantly lower hydrostatic pressure and does not rely on shear forces to obtain effective cleaning of the microelectronic boards or wafers. The high pressure water column is replaced by a low pressure liquid stream with pressures below an atmosphere. At this pressure, the lateral or shear forces are reduced by at least two orders of magnitude compared to the previously described device. Sufficient water flow, however is still present to rinse away loose or loosened debris. The diameter of the liquid stream can be on the order of 6-7 mm. Megasonic energy from a focused transducer in a chamber under low hydrostatic pressure is directed into the liquid stream near the nozzle. Typically, longitudinal waves are used, generated by a shaped piezoelectric transducer. The predominant forces of the liquid stream incident on a workpiece undergoing cleaning are now in the direction of the stagnation column of the liquid stream, i.e., longitudinal or vertical instead of shear or horizontal. The acoustic energy can be as high as several hundred watts/cm.sup.2. This type of acoustic liquid stream has been shown to be effective in a variety of other cleaning applications, including removal of tar, wax and other debris.
An example of such a megasonic wafer cleaning apparatus is described in commonly assigned U.S. Pat. No. 5,368,054 to Koretsky et al., incorporated herein by reference. An example of a commercial system that uses megasonic energy in the cleaning process is Dainippon Screen Manufacturing Company's SP-W813-AS Spin Processor for post CMP cleaning.
However, even with systems that rely on acoustic energy it is often difficult to provide and maintain the right amount of energy to loosen and remove the metal debris without damaging some of the delicate metal wiring lines.

Metal removal cleaning process and apparatus

International Business Machines Corporation