In a thickness-measuring method during a grinding process, which suppresses wear of a probe coming into contact with a chuck table subjected to self-grind and accurately grinds a workpiece, measurement of wafer thickness is performed only at the commencement and termination of grinding, and a reference probe of a reference side height gauge is separated from the upper surface of the chuck table in the practical grinding time between the commencement and termination so as to interrupt the measurement of wafer thickness, thereby significantly reducing a time of the reference probe brought into contact with the upper surface of the chuck table.

1. Field of the Invention
The present invention relates generally to a method of measuring the thickness of a thin plate-like workpiece such as a semiconductor wafer when a grinding tool is pressed against and grinds the surface of the workpiece that is held onto a chuck table for rotation. In particular, the invention relates to a contact type thickness-measuring method in which the thickness of a workpiece is measured by bringing the probes of measurement gauges into contact with two points, the surface of the workpiece and the surface of a chuck table.
2. Description of the Related Art
Some thin plate-like semiconductor substrates which become the materials of semiconductors or electronic components are made of, for example, a single-crystal material such as silicone, or of a compound containing a plurality of elements. Such substrates which were obtained by slicing an ingot of raw material are subjected to chamfering, lapping, etching and other processes. Then, one side or both sides of the substrate are ground to a target thickness. A general method of grinding a substrate involves pressing a grinding wheel against the substrate held on a rotating chuck table while measuring the thickness of the substrate. There is known substrate thickness measurement by use of a two-point contact type thickness measurement gauge which brings the probes of the thickness measurement gauges into contact with respective surfaces of the substrate and the chuck table and determines a difference between both the measurement values as a thickness (see Japanese Patent Laid-Open No. 2000-6018).
When a substrate is ground, a process called "self-grind" is performed in which the surface of a chuck table on which the substrate is placed is evenly ground by grinding machine itself. If the "self-grind" is performed, grinding marks are formed like a radial stripe pattern on the surface of the chuck table. The grinding marks have an asperity of as minute as about 1 to about 2 μm. In order to grind a substrate the probe is brought into contact with the surface of the chuck table and the chuck table is rotated as described above. At this time, if the rotation speed is relatively fast, a phenomenon occurs in which the tip of the probe coming into contact with the chuck table is worn away by the grinding marks.
If the substrate is ground and measured in thickness with the chuck table side probe worn away, then its thickness thus measured is greater than the actual one. If control is exercised such that such an error is compensated for and grinding is performed to provide a target thickness, the substrate is excessively ground as a result to provide a thickness smaller than the target thickness. In particular, the probe on the chuck table side has a high degree of wear since it is located on the outer circumferential portion of the chuck table and the outer circumferential portion is faster in circumferential velocity than the inner circumferential portion. Increased rotation speed makes such tendency noticeable.

Thickness-measuring method during grinding process


A tool structure including a container housing a spool of dental floss is provided. A dental floss filament from the spool is directed through the housing and extends through a support rod, wherein a plurality of arcuate legs are provided extending from the support rod and arranged separated relative to one another at an acute angulation. The filament is directed through a first of the legs and extends from an outer distal end of the first leg to a second one of the legs to support dental floss therebetween. A free distal end of the dental floss is secured to a lock fastener mounted to the support rod adjacent the origin of the first and second legs.

1. Field of the Invention
The field of invention relates to dental floss tool structure, and more particularly pertains to a new dental floss tool wherein the same is arranged to provide for a filament of dental floss arranged in suspension between spaced legs for use in a dental cleaning procedure.
2. Description of the Prior Art
Dental floss holder and dispenser structure is indicated in the prior art such as in U.S. Pat. Nos. 3,759,272; 5,020,554; 4,031,909; 3,519,004; and 3,525,462.
The instant invention attempts to overcome deficiencies of the prior art by providing for a tool structure maintaining dental floss in an enclosed orientation for the sanitary storage of the dental floss prior to use, whereby a length of dental floss may be dispensed therefrom and suspended between a pair of legs. In this respect, the present invention substantially fulfills this need.


Provided are a method, a non-transitory computer-readable storage device and an apparatus for managing use of a shared memory buffer that is partitioned into multiple banks and that stores incoming data received at multiple inputs in accordance with a multi-slice architecture. A particular bank is allocated to a corresponding slice. Received respective data packets are associated with corresponding slices based on which respective inputs they are received. Determine, based on a state of the shared memory buffer, to transfer contents of all occupied cells of the particular bank. Writes to the bank are stopped, contents of occupied cells are transferred to cells of one or more other banks associated with the particular bank's slice, information is stored indicating where the contents have been transferred, and the particular bank is returned to a shared pool after transferring is completed.

As link speeds and port densities increase exponentially for data center networks, it is difficult for a shared memory system to keep up with the aggregated system bandwidth. To cope with bandwidth demand, data center switches often adopt a multi-slice architecture in which each slice is responsible for buffering data from a subset of ports within a switch. Hence, the bandwidth requirement for each slice can be greatly reduced. The buffer memory is statically allocated among different slices. Although the scalability of such systems can be linear, it is limited by inter-slice communication and memory efficiency.
In a data center deployment, there is a high possibility of uneven buffer utilization. That is, not all of the slices will be equally occupied at the same time. Some slices might be running out of buffering space while other slices might have low buffer utilization. How to efficiently, but simply, use the buffer memory based on the slice-architecture is a challenging problem.

Dynamic packet buffers with consolidation of low utilized memory banks


In the thin-film transistor device: the stacked thickness of either a source electrode or a drain electrode and a corresponding one of silicon layers is the same value or a value close to the same value as the stacked thickness of a first channel layer and a second channel layer; the stacked thickness of the first channel layer and the second channel layer is the same in a region between the source electrode and the drain electrode and above the source electrode and the drain electrode; the first channel layer and the second channel layer are sunken in the region between the source electrode and the drain electrode, following a shape between the source electrode and the drain electrode; and the gate electrode has one region overlapping with the source electrode and an other region overlapping with the drain electrode.

(1) Field of the Invention
The present invention relates to thin-film transistor devices and methods of manufacturing the same, and relates particularly to a thin-film transistor device for driving and for switching in an organic electroluminescence (EL) display device and a liquid crystal display device, and to a method of manufacturing the same.
(2) Description of the Related Art
In electronic devices, such as television receivers, which use an organic electroluminescence (EL) display device or a liquid crystal display device, luminescence elements which are arranged in a matrix and configure the organic EL display device or the liquid crystal display are driven by thin-film transistor (TFT) devices.
Top gate (staggered) thin-film transistor devices, for example, are available as such a thin-film transistor device. In addition, a top gate thin-film transistor device includes a source electrode, a drain electrode, a semiconductor layer (channel layer), and a gate electrode which are sequentially stacked on a substrate. Among thin-film transistor devices, thin-film transistor devices using amorphous silicon as the material of the channel layer are common due to ease of manufacturing (see for example Patent Reference 1: Japanese Unexamined Patent Application Publication No. 6-342909).

Thin-film transistor device and method of manufacturing the same

Panasonic Liquid Crystal Display Co., Ltd.


Design forms are disclosed for 5X and 10X laser beam expanders whose lens elements consist only of plastic and liquid optical materials, which provide diffraction-limited performance without refocussing over a wavelength range from 0.4 micron to 0.8 micron.

The lens elements of laser beam expanders are ordinarily made of optical glasses. In general, optical glasses are considerably more expensive than optical-quality plastic and liquid materials.
A need has been recognized in the optical industry for reducing the cost of laser beam expanders. However, until the present invention, design forms had not been available for high-performance laser beam expanders whose lens elements consist only of plastic and liquid lens elements.

Laser beam expanders with plastic and liquid lens elements


Embodiments of the present invention are directed to a stirrer tool that includes a head component having a first plurality of projections extending substantially radially out from and substantially perpendicular to a longitudinal axis of a body portion. Head component may also have a second plurality of projections extending in a substantially distal direction away from a distal end of the body portion, and all of the projections may be made of a substantially stiff material that is flexible enough to be bent to fit through an opening in a container that is smaller in diameter than a diameter of the head component and stiff enough to mix viscous products. The projections may further be capable of being shortened by cutting off a selected length of the projections. The first plurality of projections may be configured to create a vortex mixing action and the second plurality of projections may be configured to reach and stir up sediment on bottoms and in corners of containers. The system may further include an elongate shaft, which may be coaxially aligned with, and a distal end of the elongate shaft may be attached to the head component and the proximal end of the elongate shaft may be configured to be removable held in a device to rotate the elongate shaft.

In the course of using paints, putties, co-mixed liquids, and other products that tend to separate into different layers of their constituent materials (for example, paint, wall-board mud, and the like) it is often necessary to remix the products. To do this completely it is necessary to physically reach the bottom of the container in which the product is stored to ensure any sediment that may have settled there is mixed back into the product as well as combine new materials together in the course of preparing for their application. To make sure the remixing is as complete as possible, it is necessary to be able to reach the corners of the container defined by the junction of a bottom and sides of the container. To do this without the use of large, heavy and expensive equipment has resulted in the development of alternative and portable devices for mixing these products. Unfortunately, currently available devices are limited in their ability to completely re-mix products in that they are designed to work in only one or two specific ways. For example, some are specifically designed to reach the bottom and/or corner of a container to stir up and then mix in sediment deposited there, some have multiple and multi-level projections, some are collapsible, some rely on a creating a vortex in the product, some are flexible enough to be inserted into and removed from a container through a small opening, a small few may be temporarily and/or permanently varied in their size and/or shape, and many are made of hard materials that frequently damage the container in which they are being used. In addition, the use of hard materials, for example, inflexible metal wire, restricts the size or length of the mixing head and, as a result, the action does not provide sufficient static to create a vortex or velocity to stir products and/or paints completely. However, none provide the functionality from all of the above features and characteristics.
As a result, what is needed is a stirrer tool that can reach the bottom and/or corner of any container, has multiple and multi-level projections that are collapsible to be able to be inserted into a container through an opening smaller than the circumference of the stirrer tool, uses a vortex mixing action in conjunction with a dispersion ability, and that can be temporarily and/or permanently varied in its configuration, size and/or shape, and be made of materials of sufficient strength to dislodge and disrupt materials or sediment and that will not damage the container in which it is being used.

Stirrer tool with radially and distally extending flexible projections


Token-based flow control of messages in a parallel computer, the parallel computer including a plurality of compute nodes, each compute node including one or more computer processors, including: allocating, by a token administration module to a plurality of the computer processors in the parallel computer, a number of data communications tokens; identifying all communicators executing on each computer processor, where each communicator is participating in a distinct parallel operation executing on the parallel computer; allocating, to the communicators, the data communications tokens; determining, by a communicator attempting to send data to the destination, whether the communicator has enough available data communications tokens to send the data to the destination; and responsive to determining that the communicator has enough available data communications tokens to send the data, sending, by the communicator, the data to the destination.

1. Field of the Invention
The field of the invention is data processing, or, more specifically, methods, apparatus, and products for token-based flow control of messages in a parallel computer.
2. Description of Related Art
The development of the EDVAC computer system of 1948 is often cited as the beginning of the computer era. Since that time, computer systems have evolved into extremely complicated devices. Today's computers are much more sophisticated than early systems such as the EDVAC. Computer systems typically include a combination of hardware and software components, application programs, operating systems, processors, buses, memory, input/output devices, and so on. As advances in semiconductor processing and computer architecture push the performance of the computer higher and higher, more sophisticated computer software has evolved to take advantage of the higher performance of the hardware, resulting in computer systems today that are much more powerful than just a few years ago.
Current parallel computers are running a number of processes that just a few years ago would have seemed unimaginable. For example, current parallel computers may execute millions of processes simultaneously. Processes executing on compute nodes in the parallel computer often send each other data. The flow control of that data is not always even. That is, some destinations receive more data than others. If a particular destination receives more data that it can process, efficiency is harmed for that destination as well as senders of the data.

This patent is subject to a terminal disclaimer.

International Business Machines Corporation


An image forming apparatus includes: a sheet tray; an image forming unit that forms an image on a recording sheet; a sheet transporting path that allows a transportation of the recording sheet fed from the sheet tray to the image forming unit; and a sheet detecting unit that detects a passage of a rear end, with respect to a direction in which the recording sheet is transported, of the recording sheet along the sheet transporting path. The transportation of the recording sheet is temporarily stopped at the time of, or after a predetermined time from when the rear end is detected by the sheet detecting unit. The transportation of the recording sheet is resumed on the basis of data on a size of the transported recording sheet and a timing of image formation by the image forming unit.

1. Field of the Invention
This invention relates to an image forming apparatus adapted to form an image on recording sheets sent to a predetermined position in order from a sheet tray, and more particularly to an image forming apparatus capable of forming an image in an accurate position on each of the recording sheet even when a tab and the like is provided at a front end of the recording sheet sent to the mentioned position.
2. Background Art
In an image forming apparatus adapted to form an image on a recording sheet, especially, in an image forming apparatus adapted to form a visible image on a recording sheet by selectively depositing a powdered toner on a latent image formed owing to an electrostatic potential difference, a means for regulating the recording sheet sending time so as to form an image in an accurate position on the recording sheet is employed. In an electrophotographic image forming apparatus adapted to form an image by using a toner image, and, in an electrostatic recording type image forming apparatus, a toner image is formed on an image carrier, and then sent forward by the movement of a circumferential surface of the image carrier. This toner image is then transferred onto a recording sheet directly or via an intermediate transfer member. During this time, the time at which the recording sheet is sent forward is regulated with respect to the movement of the member on which the toner image is supported, and the recording sheet is brought into contact with an accurate portion of the member on which the toner image is supported. This time regulation is conducted generally by using resist rolls which will be described below.
As shown in FIG. 4, on the upstream side of a transfer unit 101 in which the toner image is transferred onto the recording sheet, two resist rolls 102 arranged in parallel with each other and engaged each other under pressure are provided. When a recording sheet P is sent from a sheet tray 103, a front end of the recording sheet is made to impinge upon pressure engaged portions of the two resist rolls 102 stopped in advance. During this time, after the front end of the recording sheet contacts the resist rolls 102, further upstream side sending rolls 104 feed out the recording sheet P by a predetermined length, and stop with a rear portion of the recording sheet P gripped. As a result, flexure occurs between the sending roll 104 and resist rolls 102 as shown in FIG. 4, and the front end of the recording sheet is pressed against the resist rolls 102 by an elasticity restoration force of the recording sheet itself. Even though the recording sheet is sent in an inclined state during this time, the recording sheet P has a marginal length between the sending rolls 104 and resist rolls 102, so that the front end of the recording sheet P is pressed against the resist rolls 102 with the recording sheet extending at right angles to the axes of the resist rolls.
The driving of the resist rolls 102 is then started in accordance with the time at which the toner image is sent thereto, to send the recording sheet P forward. During this time, the front end of the recording sheet is held between the two resist rolls 102 at right angles to the axes thereof, i.e., the recording sheet is fed forward with a diagonal posture thereof corrected. The recording sheet is brought into contact with an accurate portion of the toner image being sent thereto, and the toner image is transferred onto the recording sheet.
However, the recording sheets used have been diversified in recent years, and a recording sheet the front end of which does not extend straight at right angles to the direction in which the front end is sent is used in some cases. In a case where such a recording sheet is used, hindrance to the sending of the recording sheet occurs. For example, when a so-called tab sheet on which a tab for putting an index thereon is provided in a projecting state is made to impinge upon the resist rolls with the tab projecting from a front end of the tab sheet, the tab sheet which has theretofore been sent forward accurately starts being sent diagonally due to the projecting tab. Moreover, the time during which the recording sheet is sent forward is delayed by a period of time corresponding to the length of the tab, so that an image cannot be transferred onto an accurate portion of the recording sheet.
In order to deal with such problems, when the forming of an image is done by not disposing the edge, on which the tab is provided, of the tab sheet on the forward side, inconveniences do not occur. However, when images are formed on both surfaces of a tab sheet, the direction in which the tab sheet is sent is reversed. Therefore, in order to transfer an image onto the rear surface of the tab sheet, the tab sheet is sent with the edge thereof on which the tab is provided directed forward, though the tab was positioned at the rear end of the tab sheet during the formation of an image on an outer surface of the tab sheet. When a tab sheet is sent so that the tab is positioned on the lateral side thereof, inconveniences occur in a certain case where after-treatments, such as hole making operations and sheet binding operations are carried out continuously.
Other means for solving the above problems are disclosed in JP-A-2003-226448 and JP-A-2003-122223. In the image forming apparatuses disclosed in these publications, an image is formed in accordance with a predetermined portion of a recording sheet being sent, and the image is transferred onto the mentioned portion of the recording sheet. Therefore, stopping the recording sheet temporarily and regulating the time for feeding the recording sheet again becomes unnecessary. In short, these apparatuses are adapted to form an image in accordance with the time at which a recording sheet is sent out, and transfer the image onto an accurate portion on the surface of the recording sheet. Therefore, even when a tab and the like is provided on a front end of the recording sheet, inconveniences do not occur during the sending of the recording sheet.

Image forming apparatus for forming an image in an accurate position


A linear amplifier circuit includes a multi-stage power amplifier that can amplify an input signal to produce an output signal, and a gain feedback control circuit coupled with the output and the input of the multi-stage power amplifier. An adjacent-channel leakage feedback control circuit can detect the output signal at the output of the multi-stage power amplifier and reduce adjacent-channel leakage in the output signal over an output power range based on the detected output signal.

The present invention relates to radio frequency power amplifiers.
Portable devices such as laptop personal computers, Personal Digital Assistant and cellular phones with wireless communication capability are being developed in ever decreasing size for convenience of use. Correspondingly, the electrical components thereof must also decrease in size while still providing effective radio transmission performance. However, the substantially high transmission power associated with radio frequency (RF) communication increases the difficulty of miniaturization of the transmission components.
A major component of a wireless communication device is the power amplifiers (PA). A PA can be fabricated on a semiconductor integrated circuit (IC) chip to provide signal amplification with substantial power. The power amplifier chip can be interconnected with certain off-chip components such as inductors, capacitors, resistors, and transmission lines for operation controls and for providing impedance matching to the input and output RF signals.
One significant challenge for power amplifiers is power consumption. As RF devices are used in longer distances and broader frequencies, the RF devices can consume power at increased rates. Batteries of the RF devices often need to be frequently recharged. Several attempts have been made to improve power amplifiers' power consumption. A power amplifier using so called "Doherty Technique" includes a plurality of serially connected power amplifiers. Another attempt utilizes a number of power amplifiers arranged in a parallel circuit. Another design attempts to reduce power amplifiers' power consumption using quadrature balanced amplifiers. These designs, however, usually cannot provide high quality signals over a wide output power range and a wide frequency range.

RF power amplifier with linearity control


An automated flat mail piece comprising a bendable envelope and a bendable insert tray disposed inside the cavity of the bendable envelope that satisfies USPS requirements for automated flats. The insert tray has a rectangular base with a perforated line disposed centrally from each edge to its respective opposing edge, dividing the base into four segments. A flap is integrally connected to the base by two walls extending at substantially right angle from the base. A set of three bend-enabling score lines disposed co-linear with the longitudinal and transverse bend axes of the envelope enable lengthwise and widthwise bending of the envelope. Diagonal stress relief score lines cooperate with bend enabling score lines to lessen the effects of a crease. A stress relief score line is disposed diagonally extending from an outer bend-enabling score line at the envelope edge to a center bend-enabling score line.

1. The Field of the Invention
The present invention is directed generally to packages, and in particular, a package that converts a parcel or a not automated flat mail piece to an automated flat mail piece.
2. Background Art
Envelopes have long been known in the art as a quick and efficient way of containing small articles for mail delivery. It has become increasingly important to move away from mailing articles that require manual sorting to mailing articles that are machine sortable. An automated flat mail piece requires little to no human intervention during processing and sorting, resulting in lower mailing costs than manually handled mail pieces.
The United States Postal Service (USPS) requires that an automated flat mail piece conform to certain mail regulations. One of the requirements to enable automated flat mail processing is that a mail piece must bend easily when subjected to a transport belt tension of 40 pounds around an 11-inch diameter turn. In order to qualify as an "automated flat," the USPS also requires that the mail piece thickness to be no less than 0.25 inch and to not exceed 0.75 inch. If the shipper fails to meet the strict USPS requirements, it may be responsible for surcharges for mail pieces destined for automated mailing equipment that fail to meet USPS's automated flat mail requirements, and/or cause the machines to experience stoppages due to the nonconforming mail pieces. For a non-flat three dimension article, this requirement poses a challenge: to provide an envelope system that is both bendable and can hold articles securely without damage to the article. None is presently known in the art.
Thus, there is a need for a device which overcomes the limitations and drawbacks of the prior art by meeting the USPS requirements for a system that converts a parcel or not automated flat mail piece to an automated flat mail piece.


A direct current sum bandgap voltage comparator for detecting voltage changes in a power supply. The direct current sum bandgap voltage comparator includes a summing node, current sources connected to the summing node and the power supply, and an indicator circuit connected to the summing node. Each current source supplies a current to the summing node wherein the summing node voltage level is responsive to the currents supplied. The indicator circuit is responsive to changes in the summing node voltage level and generates at an output a logical signal at one state when the summing node voltage level is greater than a predetermined value and generates the logical signal at the output at another state when the summing node voltage level is less than the predetermined value, the predetermined value corresponding to a preselected power supply voltage.

1. Field of the Invention
The present invention relates to integrated circuits and in particular to MOS integrated circuits. Still more particularly, the present invention relates to bandgap reference circuits in insulated gate FET semiconductor integrated circuits.
2. Description of the Prior Art
In some situations it is desirable to provide retention of data in integrated circuits such as memory devices. A number of circuits are commercially available for retaining data in SRAMS when power is removed. These devices are often known as "zero power circuits". Typically, in a zero power circuit, the contents of the circuit are protected in the event that the power supply voltage to that circuit drops below some predetermined or preselected threshold voltage. This protection may be accomplished by switching the circuit from the primary power supply to a secondary power supply, typically an integral battery, when the voltage of the primary power supply drops below the selected threshold voltage. Secondary or backup power supplies are well known, as may be seen in U.S. Pat. Nos. 4,381,458 and 4,645,943.
Power controller circuits exist, which provide automatic sensing of a primary power source voltage. These power controller circuits provide automatic switching to a secondary power source when the primary power source voltage drops below a predetermined threshold voltage. An example of one such system may be found in U.S. Pat. No. 5,121,359, which describes a programmable logic device with a backup power supply that is automatically provided when a power loss at an input pin is detected. U.S. Pat. No. 4,654,829 discloses a portable non-volatile memory module, using a comparator and switching circuitry to switch between a primary power supply and a secondary power supply, such as a battery power supply.
Past approaches in setting or selecting the voltage level in a zero power circuit has involved the use of many bipolar devices, large resistors, oscillators, switched capacitors, autozero devices, etc. A bandgap reference circuit is one circuit that may be used to set that voltage level. One drawback with a typical bandgap reference circuit is that a large number of devices are needed for implementation. As a result, a large amount of area on a semiconductor chip is required. In addition to the area problem, typical bandgap reference circuits also are fairly sensitive to noise within the circuit. For example, active memory circuits are usually noisy and known bandgap circuits used with active memories circuits are usually sensitive to the noise generated.
Therefore it would be desirable to have a circuit that is smaller, simpler, and less sensitive to noise.

Direct current sum bandgap voltage comparator


A transceiver includes a transmitter and a receiver. The transmitter includes an ECC encoder and a data frame generator. The ECC encoder is configured to generate an ECC parity from user data and at least one bit from a syncmark. The data frame generator is configured to generate a data frame for transmission from the syncmark, the user data, and the ECC parity. The receiver includes a detector, an inverter, and a decoder. The detector is configured to detect a received syncmark in a received data frame. The received data frame includes the received syncmark, received user data, and received ECC parity. The inverter is configured to selectively invert a sequence. The sequence includes the received user data, the received ECC parity, and at least one bit from the received syncmark. The decoder is configured to decode one of the sequence or the inverted sequence.

1. Field of the Invention
The present invention relates generally to data transmission, and more particularly to error detection in data transmission.
2. Description of Related Art
FIG. 1 illustrates a prior art data frame structure and a data transmission process. At a transmitter 1, a data frame 110 may start with a preamble field 1101, which is followed in sequence by a syncmark field 1102, a user data field 1103 (also referred to as payload), and an error correcting code (ECC) parity field 1104. The syncmark may be a unique series of 0 and 1 and may be used to identify, preferably with high reliability, the start of user data to be transmitted. Since the user data field is immediately after the syncmark, as long as the syncmark is detected, the start of user data will be located. The ECC parity may be generated by an ECC encoder 101 from the user data.
A receiver 2 may be informed of the syncmark in advance, and may detect the start of user data by searching for the syncmark. At the receiver 2, a data frame from the transmitter 1 may first enter a syncmark and user data detector 102. If the syncmark is not found, the receiver 2 may claim failure and report error status. If the syncmark is found, the received bits corresponding to the user data 1103 and ECC parity 1104 may be fed from the syncmark and user data detector 102 to an ECC decoder 103. The ECC decoder 103 may try to decode and/or correct errors in its input. When there is no error, or there are errors but the errors are correctable, the ECC decoder 103 may output decoded user data. Otherwise, the ECC decoder 103 may claim failure and report error status.
The error detection capability of an ECC mainly depends on the number of bits in the ECC parity. The more bits in the ECC parity, the more errors the ECC may detect and/or correct. Thus, one known solution to enhance the error detection capability of an ECC is to use an ECC parity which is sufficiently long. However, when the physical space for a data frame is fixed, a long ECC parity may lead to higher bit density, which in turn may degrade the performance of the ECC. Therefore, it may be desirable to provide a method and apparatus that improve error correction capability of the ECC without costing data bit density.

Method and apparatus for enhancing error detection in data transmission


A method of manufacturing a seal assembly for attachment to a vehicle having a securing point spaced from a vehicle point at a distance with an apparatus having first and second receptacles defining a cavity, and a bracket apparatus defining a bracket cavity, including: forming a first strip having a first body with first ends; forming a second strip having a second body with second ends; positioning one first end into the first receptacle with the first body adjacent to the bracket cavity; positioning one second end into the second receptacle; forming a molding bonding the strips together to define a mold point; forming a bracket with a receiver at a receiver point, and an interface bonded to the first body spaced such that a distance between the receiver point of the bonded bracket and the mold point is equal to the distance between the securing and vehicle points.

Conventional seal assemblies are used in a number of different industries to provide a seal between different components which may be movable relative to one another. By way of non-limiting example, seal assemblies such as weatherstrips, weatherseals, glassrun moldings, window seals, and the like are used in the automotive industry to seal between a vehicle door defining a window opening, and a glass panel supported for sliding movement relative to the door to selectively close the window opening. These conventional seal assemblies may be operatively attached to different portions of the vehicle in a number of different ways, such as with fasteners, clips, and the like.
Those having ordinary skill in the art will appreciate that seal assemblies may be manufactured in a number of different ways to suit specific vehicle application requirements. To this end, conventional seal assemblies are formed from one or more extruded members which are molded together, such as with a plastic injection process, which bonds the extruded members together at a predetermined location corresponding to a portion of the vehicle, such as at a corner of the window opening, to form a molded seal assembly. In order to facilitate attachment to the vehicle, various types of clips, locators, and/or brackets are often subsequently attached to the molded seal assembly at predetermined locations which correspond to fastening locations of the particular vehicle. To this end, holes or other formations may be defined in one or more of the extruded members prior to molding, and clips, fasteners, locators, and the like may be subsequently installed into the holes/formations after the molded seal assembly has been formed.
While methods of manufacturing seal assemblies known in the related art have generally performed well for their intended purpose, there remains a need in the art for improved methods of manufacturing.

Method of manufacturing a window seal assembly with a molded bracket

Henniges Automotive Sealing Systems North America, Inc.


Herein disclosed is a centrifugally cast pole having a substantially uniform wall thickness along the long axis of the pole. During centrifugal casting, molten metal is poured inside a rotating, tapered mold. As chilled liquid is poured over the outside of the rotating mold, the metal forms, or paints, to the contour of the mold interior creating a metal pole. By precisely controlling casting gyrations such as the spin, travel, pitch, and yaw of the rotating mold and the calibration and physical mechanisms of the casting machine, hollow, tapered, tubular metal poles are produced with previously unknown uniformity of wall thickness. The controlling principles, designs, and mechanisms of this centrifugal casting method enable wall uniformity to extremely high tolerances. By extension, the ability to precisely control the metal volume painted inside the mold allows, as a design choice, wall thickness variation in any embodiment if so desired.

1. Field of the Invention
This invention relates generally to hollow structural members and more specifically to hollow utility poles having tapered external dimensions and substantially uniform wall thickness.
2. Description of the Prior Art
The geometric shape of tapered poles in high stress, high lateral-force environments typically encountered in the utility industry inherently provides the greatest cross-sectional strength at or near the base of the pole where reactive forces tend to combine and converge.
Problems associated with the use of wooden poles within the utility industry are numerous and well documented. These problems include ground line decay, the tendency of wooden poles to bend or arc under high lateral forces (thereby requiring the use of guying cables, anchors and other auxiliary hardware), deterioration caused by birds and other animals, vibration damage to attached hardware and fixtures, shortages of suitable trees for producing large poles, and high breakage rate due to natural and manmade forces. Additionally, wooden poles as a general rule must be replaced after approximately 20-30 years of service. Of particular note, replacement and disposal of wooden poles is a mounting, exorbitant liability for companies, especially when these poles cannot be incinerated due to regulatory mandates. Further, some utility companies have resorted to wrapping their wooden poles in wire mesh to prevent damage to the poles by birds and other animals.
Other companies have resorted to using hollow concrete poles, particularly with regard to high voltage electric transmission systems, in order to overcome some of the difficulties associated with wooden poles. Concrete utility poles, however, are expensive to produce, are very heavy and require special heavy-duty equipment to load, transport, unload and install. Further, due to strength requirements, concrete poles are usually solid at the top, where the pole has its smallest diameter. Moreover, field modifications of concrete poles are generally very time consuming, cumbersome and thus very costly.
Steel utility poles are currently available in the market. Steel poles are typically produced by cutting thin and malleable steel plates and forming the plates, using metal brakes and other hot and/or cold metal shaping methods, into two multi-sided halves which are then welded together. Such poles are quite expensive to produce and, as a consequence of the thin walls necessary to form them, result in poles having relatively large base diameters in order to achieve the necessary strength to be used in high stress, high lateral-force situations such as those subject to utility poles. Further, wall thickness can be varied only sectionally, if at all.
Aluminum alloy utility poles are also available. However, these poles are generally appropriate for low stress, single-use application, such as highway lighting. Further, aluminum poles are not currently formed by centrifugal casting methods and are typically produced by hot or cold metal-shaping methods. Moreover, aluminum poles do not have the necessary qualities or strength to be used in high lateral-force environments, such as those to which utility poles are subjected.
Ductile iron has characteristics which are ideal for use in the utility pole environment. For example, ductile iron has a superior strength/weight ratio, is machineable, resilient (as opposed to brittle), has favorable damping properties, is rust proof and is cheaper than aluminum and concrete. Therefore, if centrifugally cast into geometric shapes necessary for utility pole applications, ductile iron would provide a virtually maintenance free, extremely long life (many 100+ year old ductile iron water mains are still in use), low cost utility pole which effectively overcomes the problems and difficulties associated with other utility poles as discussed hereinabove.
Centrifugal casting offers additional benefits over alternative production techniques such as metal forming. For instance, centrifugal casting produces a seamless pole, which ensures overall strength in high stress, high lateral-force environments. Furthermore, centrifugal casting allows a large volume of poles to be produced inexpensively through a mechanized process involving little human labor. Since long, seamless sections can be cast in a single pass, subsequent joining procedures during manufacture or field installation are reduced or eliminated. Also, centrifugal casting produces a much more precise pole than that created through metal forming, and is capable of producing poles within tolerances of 0.001 mm. In summary, centrifugal casting produces stronger, less labor-intensive poles that are more easily mass produced for a wider variety of applications.
Prior to the present invention, centrifugal casting of tapered metal utility poles (including ductile iron) has been limited by the casting technology. Single-speed casting methods (such as that disclosed in Applicant's prior U.S. Pat. No. 5,784,851) prevented the metal infusion from dispersing properly such that the amount painted on the inside of the mold as it spins and travels can be deposited end-to-end uniformly to high tolerances (0.001 mm.). This has meant that centrifugal casting of tapered poles was only slightly more versatile than metal rolling, though there are other advantages mentioned hereinabove. The present invention overcomes this limitation by introducing a variable-speed, variable-infusion casting method, whereby the metal-painting is precisely controlled by increasing or decreasing the metal pouring rate and the spin speed of the mold. Depending upon the desired specifications, poles can be formed with walls that are thick at bottom and thin at top, that vary in thickness at specified points, or that are substantially uniform in wall thickness along the long axis of the pole.
Further, the present invention allows production of poles that fulfill specific application requirements. For example, while some applications require variable thicknesses (thin at the top, thick at the ground line to resist line loads and corrosion), other applications may require uniform thickness for maximized structural support. The present invention also fulfills applications that require extreme or variable heights, in that the poles may be cast with slip-jointed pole sections, whereby the tapered section of one pole can be secured into the butt end of another pole to reach specified effective pole lengths. Additionally, special applications may require further enhancement of the pole during or post-casting including, but not limited to, wind-resistant texturing, mount flanges, hardware and fixture access holes or panels, and top-end caps.


A beverage can dispensing method and apparatus for use in a refrigerator comprising three angularly disposed shelves, two said shelves being angularly disposed from front to rear to enable cans to roll from front to rear. A third shelf angularly disposed in a downward direction from the rear to the front to allow cans to descend from said first two shelves to the third shelf and ultimately to the position of ejectment from the front of the dispenser and means cooperable therewith to raise a can for ejectment by reason of the pressure of other cans on said third shelf against a can in the ejectment position.

I. Field of the Invention
This invention is in the general field of beverage dispensing; the invention is more particularly directed to a method and apparatus for beverage dispensing, primarily, but not exclusively, designed for home use; the invention is even more particularly directed to a beverage dispensing method and apparatus wherein the apparatus is suitable to be mounted within a household refrigerator and designed to carry fifteen cans of beverage which self-feed, by gravity, to a dispensing arrangement.
II. Description of the Prior Art
I know of only one item which might be considered prior art as compared to my invention. That particular article is illustrated in FIG. A of the accompanying drawings, and is described in more detail in connection with the description of that figure of the drawing.

Beverage dispensing method and apparatus


Conductive films with transparency characteristics are provided. In accordance with various example embodiments, a transparent conductive film includes an inorganic nanowire mesh embedded in an organic substrate layer. The embedding may involve, for example, embedding a majority of, or substantially all of the nanowire mesh in the organic substrate layer to facilitate a resulting surface roughness of the combined nanowire mesh-polymer that is less than a surface roughness of the mesh alone (e.g., or otherwise embedded), and in turn facilitates desirable conductivity characteristics.

A variety of materials have been used for transparent conductors (conductors passing at least some, if not a majority, of light incident thereupon). Such conductors are used, for example, with optoelectronic devices, displays and touch screens. One type of material that has been used with these devices is tin-doped indium oxide (ITO). However, ITO is relatively expensive, can be expensive to form, and can further be brittle. Other materials have been difficult to implement, due to a variety of characteristics such as cost and difficulty in their implementation, or insufficient performance (e.g., insufficient transparency, insufficient conductivity, and related tradeoffs).
These and other issues remain as a challenge to a variety of methods, devices and systems that use or benefit from transparent conductive films.

The Board of Trustees of the Leland Stanford Junior Univerity


In order to protect a monocrystalline superalloy rich in rhenium against corrosion whilst avoiding the formation of progressive secondary reaction zones, a layer (3) formed of tungsten and cobalt is deposited on its surface before aluminisation treatment.

The invention relates to a method of protecting against corrosion a monocrystalline superalloy containing at least one refractory metal, in which is formed on the surface of the superalloy a coating containing aluminium.
With the purpose of optimising temperature-resistance and oxidation-resistance of parts of turboengines composed of superalloys, these are covered with a protective coating containing aluminium in order to form at the surface of the part covered a protective aluminium oxide. This coating may be formed by conventional aluminisation treatment, which may be either high-activity or low-activity, e.g. low-activity vapour-phase aluminisation. However, the aluminium present in this coating migrates as much towards the surface of the part where it renews the oxide layer as towards the superalloy substrate, of which it impairs the features of use (the aluminium is then the chemical motor of this impairment) and in so far reduces the amount available to renew the oxide layer.
In order to improve the mechanical properties of turboengine parts composed of nickel-based superalloys, compositions have been developed which are rich in refractory elements and at the limit of stability, the limit of solubility of these elements in they phase being affected.
After the development of a coating on this type of superalloy with a γ/γ′ structure, there appear in the layer known as the "diffusion layer" located between the coating and the substrate microstructural weaknesses leading to the formation of phases said to be TCP (Topologically Close Packed) and progressive secondary reaction zones (SRZ). These form in the part of the diffusion layer closest to the substrate, known as the interdiffusion zone.
The affect of the secondary reaction zones on the mechanical properties is still poorly understood. However, the mere fact that a secondary reaction zone, whose thickness may vary from 20 to 100 μm according to the quantity of available aluminium, forms under the diffusion zone, whose thickness is typically of the order of 20 μm, reduces by that amount the thickness of healthy alloy. This may be particularly harmful in the case where a thin-walled component is being used, such as cooled blades. Therefore, numerous work has been carried out to identify the causes of secondary reaction zones and to reduce them, if not eliminate them.
The nature of the substrate and its chemical composition (in particular monocrystalline alloy rich in rhenium and low in cobalt) seem to play a part in determining the appearance of secondary reaction zones.
In the conditions of use of the parts, the secondary reaction zones increase towards the interior thereof, further reducing their mechanical strength over the course of time.
Local stresses also favour the appearance of secondary reaction zones. These local stresses are due to operations prior to any coating (sand-blasting in particular) (mechanical motor).
The analysis of a secondary reaction zone shows that it is formed of filaments γ in a matrix γ′. An incoherent grain boundary separates the secondary reaction zones from the γ/γ′ structure of the superalloy.
Some authors have sought to overcome the mechanical motor by reducing the stresses by recrystallising a thin surface zone of the superalloy before proceeding to the stages of forming the coating (Rebecca A MacKay, Ivan E Locci, Anita Garg, Frank J Ritzert, Techniques Optimized for Reducing Instabilities in Advanced Nickel-base Superalloys for Turbine blades, RT2001 NASA Technology report, NASA TM 2002-211333; W H Murphy, W S Walston, Method for making a coated Ni base superalloy article of improved microstructural stability, U.S. Pat. No. 5,695,821).
Others specify changes in composition (U.S. Pat. No. 5,695,821; K S O'Hara, W S Walston, E W Ross, R Darolia, Nickel base superalloy and article, U.S. Pat. No. 5,482,789) or carbiding treatments (J Fernihough, Process for strengthening the grain boundaries of a component made from a Ni based superalloy, U.S. Pat. No. 6,471,790; J Schaeffer, A K Bartz, P J Fink, Method for preventing recrystallisation after cold working superalloy article, U.S. Pat. No. 5,598,968), or of nitriding (K S O'Hara, W S Walston, J C Schaeffer, Substrate stabilisation of superalloy protected by an aluminium-rich coating, U.S. Pat. No. 6,447,932). These latter specifications have the aim of creating carbides or nitrides which would pin down the secondary reaction zones and would inhibit their progression.
Kelly et al. (T J Kelly, P K Wright III, Article having a superalloy protective coating and its fabrication, U.S. Pat. No. 6,641,929) propose to deposit a metal layer by cathode sputtering before the protective operation. This layer is no other than a second superalloy, the γ/γ′ alloy interdiffusion not leading to the formation of secondary reaction zones.
Finally, R G Wing teaches (Method of aluminizing a superalloy, U.S. Pat. No. 6,080,246) that it is possible to stabilise the composition of the surface of superalloys heavily enriched in refractory elements (Re and/or Ru) by the diffusion of a deposit of cobalt or a deposit of chromium, the latter being preferably deposited by thermochemical means (chromising). However, in the case where cobalt is used, although this technique makes it possible to do away with secondary reaction zones, it leads to the formation of a protective coating heavily enriched in this element. In an article by Warnes et al. (Cyclic oxidation of diffusion aluminide coatings on cobalt base super alloys, Bruce M Warnes, Nick S DuShane, Jack E Cockerill, Surface and Coatings Technology 148 (2001) 163-170), it is stated in conclusion that the coatings obtained by diffusion on cobalt-based alloys (the aluminides of cobalt) are probably insufficient to protect the turbines in operation. This technique therefore makes it possible to retain the microstructure of the alloy but to the detriment of its resistance to oxidation.

Protective coating for monocrystalline superalloy

ONERA (Office National d'Etudes et de Recherches Aerospatiales)


A system and method allows for multiple modes of termination, including termination by a fixed value that is preprogrammed, and by a variable value that can, for example, be measured and determined by a self-calibration circuit. Multiple termination values can be achieved within a single device. This configuration is especially applicable to devices that have different loadings for address and data signals, for example in a configuration having a common, shared address bus, and multiple, localized data buses.

This application claims the benefit of the priority date of Korean Application No. 2002-28845, filed May 24, 2002.
The present invention relates to an integrated circuit in a semiconductor memory device for controlling impedance matching in the semiconductor memory device, and particularly to a semiconductor memory device for controlling on-die (on-chip) termination and further to a control circuit thereof.
CPUs, semiconductor memory devices, and gate arrays find application in electronic devices such as personal computers, servers, and workstations. In most cases, the devices include input pads and related circuits for inputting signals from an external source, and output pads and related circuits for outputting signals to an external source.
As the integration and speed of electronic devices increases, the swing width, or peak-to-peak voltage, of interface signals between the devices necessarily decreases. Reduction of swing width minimizes the time delay involved in signal transfer. However, as the swing width of signals is decreased, the influence of external noise on the signals also increases, and signal reflection from the receiving terminal becomes increasingly critical due to impedance mismatch. The impedance mismatch may be generated due to external noise, variation of the power supply, variation of the operating temperature, and variation in manufacturing process. If an impedance mismatch occurs, it is difficult to obtain high transfer speed in data transfer systems, and output data from output terminals of semiconductor memory devices may vary or may be unreliable, causing data transfer failure. In view of this, receiving terminals of devices are designed to include signal termination circuitry, referred to herein as on-chip termination or on-die termination, that mitigate impedance mismatch. Such impedance matching circuits and related circuits are located proximal to the input/output pads of the devices. At the transmitting end of a data transfer system, source termination is commonly employed, while at the receiving end, parallel termination is commonly employed.
Semiconductor memory devices such as DDR SDRAMs (Double Data Rate Synchronous Dynamic Random Access Memories) adopt termination circuits implemented with resistor units having a fixed value as illustrated in FIG. 1. FIG. 1 demonstrates a conventional arrangement for a termination circuit for terminating bonding pads in an integrated circuit (IC). Referring to FIG. 1, a plurality of input pads PD1, PD2, PD3, . . . are connected to a plurality of data nodes RD1, RD2, RD3 . . . via a plurality of termination circuits 10, 20, 30, . . . respectively.
FIG. 2 is a schematic illustration of a typical example of the termination circuit block BA1 of FIG. 1. The termination circuit 10 is comprised of resistors R1, R2 connected to the input pad PD1 of the receiver. Resistor R1 is connected to a power supply VDD, while resistor R2 is connected to ground VSS, An input circuit, such as an input buffer, may be connected to node RD1 in parallel with the termination circuit 10. In one example, if the termination circuit 10 is designed to have an parallel sum impedance value of 60 ohms, then the value of each resistor R1, R2 is 120 ohms.
The conventional on-chip termination circuit has a fixed value of resistor as shown in FIG. 2, and the impedance value therefore cannot be adjusted to compensate for variations in the external environment. Thus, a variable termination operation is not achieved by this configuration.
The present invention is directed to a system and method that allows for multiple modes of termination, including a fixed value that is preprogrammed, and a variable value that can, for example, be measured and determined by a self-calibration circuit. The present invention also provides for the possibility of multiple termination values within a single device. This is especially applicable to devices that have different loadings for address and data signals, for example in a configuration having a common, shared address bus, and multiple, localized data buses.
In one aspect, the present invention is directed to a control circuit for controlling the impedance of a pad termination comprising: a first input for inputting a variable impedance value; a second input for inputting a fixed impedance value; and a selector for selecting one of the fixed impedance value and the variable impedance value in response to a selection signal. The selector further outputs a selected impedance value to a pad termination circuit that provides the impedance of the pad termination in response to the selected impedance value.
The fixed impedance value may be generated in response to an open or closed state of a fuse, hard-wired state, or bonding state. The fixed impedance value may comprise a first fixed impedance value and third input may be provided for inputting a second fixed impedance value. In this case the selector selects one of the first fixed impedance value, the second fixed impedance value and the variable impedance value in response to the selection signal, and outputs the selected impedance value to the pad termination circuit.
A fourth input may be provided for inputting a deactivation impedance value, in which case the selector selects one of the fixed impedance value, the variable impedance value, and the deactivation impedance value in response to the selection signal, and outputs the selected impedance value to the pad termination circuit.
The pad termination circuit may apply the deactivation impedance value by removing the applied impedance. The selector may comprise a multiplexer. The variable impedance value may be generated by a self-calibration circuit.
The self-calibration circuit preferably comprises: a reference node that is coupled to a bonding pad having a reference impedance; a first comparator having a first input coupled to the reference node and a second input coupled to a reference voltage, the comparator comparing the first input and the second input to generate a comparison output; and a plurality of impedance loads in parallel between the reference node and a first reference voltage; the plurality of impedance loads being selectively activated in response to the comparison output to provide a combined impedance that substantially matches the reference impedance.
The first and second impedance values preferably comprise a plurality of binary bits. The pad termination circuit comprises a bank of resistors, individually selectable according to the binary bits of the first or second impedance values. The plurality of resistors have resistance values that are binary multiples of each other and are connected to a common node that is coupled to a bonding pad, and the impedance of the pad termination is determined by the combined selected resistance values.
The selected impedance value comprises a first selected impedance value and a second selector may be included for receiving the first selected impedance value, and for outputting a second selected impedance value to a second pad termination circuit that provides a second impedance of a second pad termination in response to the second selected impedance value. The second selected impedance value may be one of the same as the first selected impedance value, a multiple of the first selected impedance value, a deactivation value, or may be independent of the first selected impedance value. One of the first impedance value and second impedance value may be used for termination of one of data and address pads and the other of the first impedance value and second impedance value may be used for termination of the other of data and address pads.
At least one of the first and second selected impedance values may be further used for termination of command signal pads. The command signal pads may comprise pads for at least one of a chip select signal (CSB), a row address signal (RASB), a column address strobe signal (CASB) and a write enable signal (WEB).
The selection signal is preferably generated in response to a mode register set (MRS) command used for setting the operation mode of a memory device.
The impedance value may comprise pull-up and pull-down impedance values.
In another aspect, the present invention is directed to a control circuit for controlling the impedance of a pad termination at first and second circuit pads comprising a first circuit and a second circuit. The first circuit generates a first selected impedance value and comprises a first input for inputting a variable impedance value; second input for inputting a fixed impedance value; and a selector for selecting one of the first fixed impedance value and the variable impedance value in response to a selection signal, and for outputting a first selected impedance value to a first pad termination circuit that provides the impedance of the first circuit pad termination in response to the first selected impedance value. The second circuit generates a second selected impedance value and comprises: a third input for inputting the first selected impedance value; and a selector, in response to the first selected impedance value, for outputting a second selected impedance value to a second pad termination circuit that provides the impedance of the second pad termination in response to the second selected impedance value.
The second selected impedance value may be one of the same as the first selected impedance value, a multiple of the first selected impedance value, a deactivation value, or is independent of the first selected impedance value. The one of the first impedance value and second impedance value may be used for termination of one of data and address pads and the other of the first impedance value and second impedance value may be used for termination of the other of data and address pads.
The fixed impedance value may comprise a first fixed impedance value and the first circuit may further comprise a fourth input for inputting a second fixed impedance value, and wherein the selector selects one of the first fixed impedance value, the second fixed impedance value and the variable impedance value in response to the selection signal, and outputs the selected impedance value to the first pad termination circuit.
The first circuit may further comprises a fifth input for inputting a deactivation impedance value, in which case the selector may select one of the fixed impedance value, the variable impedance value, and the deactivation impedance value in response to the selection signal, and outputs the selected impedance value to the first pad termination circuit.
In another aspect, the present invention is directed to a method for controlling the impedance of a pad termination comprising: inputting a variable impedance value at a first input; inputting a fixed impedance value at a second input; and selecting one of the fixed impedance value and the variable impedance value in response to a selection signal, and outputting a selected impedance value to a pad termination circuit that provides the impedance of the pad termination in response to the selected impedance value.
In another aspect, the present invention is directed to a method for controlling the impedance of a pad termination at first and second circuit pads comprising: generating a first selected impedance value comprising: inputting a variable impedance value at a first input; inputting a fixed impedance value at a second input; and selecting one of the fixed impedance value and the variable impedance value in response to a selection signal, and outputting a first selected impedance value to a first pad termination circuit that provides the impedance of the first circuit pad termination in response to the first selected impedance value. A second selected impedance value is also generated, comprising: inputting the first selected impedance value at a third input; and outputting, in response to the first selected impedance value, a second selected impedance value to a second pad termination circuit that provides the impedance of the second pad termination in response to the second selected impedance value.

Circuit and method for controlling on-die signal termination


Semicrystalline sulphonic fluorinated ionomers having an equivalent weight higher than 700 g/eq, up to 1,700, comprising:

The present invention relates to sulphonic fluorinated ionomers and membranes obtained therefrom, said membranes usable also at high temperatures, of the order of 100xc2x0 C. -180xc2x0 C., in electrochemical applications, for example in fuel cells.
Specifically, the invention relates to membranes of sulphonic fluorinated ionomers having even very thin thicknesses up to a limit lower than 5 xcexcm and having a high hydration degree and good mechanical properties under the use conditions.
More specifically, the sulphonic fluorinated ionomers used for the membrane preparation have equivalent weight, higher than 700, preferably between 720 and 1,700. Said membranes show, the equivalent weight being equal, an improved hydration degree compared with those of the prior art, combined with good mechanical properties.
The sulphonic fluorinated ionomers of the invention are partially crystalline and have an equivalent weight (EW) as above.
It is known in the prior art the use of the class of polymers called with the term ionomers in electrochemical applications, such for example in fuel cells, chloro-soda cells, lithium batteries, electrodialysis and in reactors in which the ionomer acts as a solid catalyst. Said applications implie the ionomer contact with an aqueous or polar liquid having affinities with the ionic functional groups of the ionomer.
In electrochemical applications, for example in fuel cells, there is a direct correlation between the ionomer conductivity and the water retention of the ionomer. The polymer ionic conductivity, besides being increased by a higher presence of ionic groups in the polymer, results significantly increased also by a larger amount of water that the polymer can retain (hydration degree).
The ionomer/membrane for the industrial application must be activated before the use, wherefore the chemical transformation of the precursor groups xe2x80x94SO2F into the corresponding ionic groups xe2x80x94SO3H is necessary. The membrane activation is carried out first by contacting with an alkaline aqueous solution and then with an acid solution (see later on).
In the prior art, to obtain membranes with sufficient physical integrity, polymers having an equivalent weight of about 1,100 are usually used. An example of such membranes is represented by the commercial product NAFION(copyright), used in the fuel cells. Said membranes, to have a good physical integrity, are typically obtained with an ionomer having equivalent weight of about 1,100. Such membranes show a not high conductivity. Besides, if said membranes are used under dehydration conditions, or with unsaturated feeding fluids to the cell, in particular at cell temperatures higher than 100xc2x0 C., they tend to dehydrate and the membrane conductivity is drastically reduced. Consequently the NAFION(copyright) membranes are not effectively usable, in particular at temperatures higher than 100xc2x0 C. and under dehydration conditions of the feeding fluids to the cell.
The sulphonic ionomers described in the prior art do not allow to obtain membranes with an optimal combination of good physical integrity and high hydration. In particular in the car industry the need is felt to have available ionomeric membranes having a very high conductivity. This is obtainable when the membrane shows high hydration and good mechanical properties so as to be able to manufacture the membrane in extremely thin thicknesses, for example from 5 to 80 xcexcm. Furthermore membranes having a very high conductivity allow to generate the same electric power with a smaller membrane surface. This is extremely desired in the car industry since it allows to reduce the size and thus the stack weight and cost. Besides, very thin membranes better resist critical dehydration conditions, since the water generated at the cathode side can more easily migrate to the anode side. Furthermore the dehydration is much higher as the cell working temperature is higher, the humidification degree of the feeding fluids thereto being equal. A high cell temperature, for example higher than 100xc2x0 C., is desirable since it allows a more effective heat exchange.
Besides, the fuel cells of the prior art use very pure hydrogen not to have poisoning of the platinum-based electrodes. Indeed if reforming hydrogen is used, thus containing CO, there is a rapid poisoning of the platinum. According to the prior art, therefore, the hydrogen from reforming must be purified from CO before being used in the fuel cells. This phenomenon is remarkably reduced when the cell works at temperatures from 110 to 120xc2x0 C., and it is practically absent at working temperature of about 150xc2x0 C.
Therefore it is desirable that the membrane shows improved hydration properties, can be used also at high temperature, for example higher than 100xc2x0 C., and shows improved mechanical properties so as not to lose its physical integrity even in extremely thin thicknesses.
Tests carried out by the Applicant have shown that with the ionomers reported in the prior art, the membranes do not show said property optimal combination.
Said membranes must be available for wide range applications, such for example in the automotive field, and therefore they must be obtainable by a process which allows its production on a large scale by continuous processes having a high efficiency, reliability and reproducibility.
The need was therefore felt to have available sulphonic fluorinated ionomers with EW higher than 700, and up to 1,700, having improved hydration properties combined with high mechanical properties able to give also thin membranes having a thickness up to a lower limit of 5 xcexcm, usable both at room temperature and at high temperature (as above defined), without substantially compromising the physical integrity of the membrane.
The Applicant has surprisingly and unexpectedly found sulphonic fluorinated ionomers capable to solve the above technical problem.
An object of the present invention are semicrystalline sulphonic fluorinated ionomers having an equivalent weight higher than 700 g/eq, up to 1,700, preferably 720-1,500, comprising:
(A) monomeric units deriving from one or more fluorinated monomers containing at least one ethylene unsaturation;
(B) fluorinated monomeric units containing sulphonyl groups xe2x80x94SO2F in such amount to give the above equivalent weight, deriving from F2Cxe2x95x90CFxe2x80x94Oxe2x80x94(CF2)qxe2x80x94SO2F, q being an integer equal to 2 or 3;
and having the following properties for a TFE/(B) copolymer wherein q=2:
hydration, (see hereafter) expressed in % of H2O at 100xc2x0 C. absorbed by the film prepared with the ionomer and after transformation from the xe2x80x94SO2F form into the xe2x80x94SO3H form, having the following values:
The invention ionomers, for a TFE/(B) copolymer wherein q=2, show film extrudability, under the xe2x80x94SO2F form, with thickness of 20 xcexcm having good mechanical properties.
The invention ionomers, for a TFE/(B) copolymer wherein q=2, show furthermore a melt flow index comprised between 0.01 and 100 g/10xe2x80x2, with a load of 5 kg measured at 280xc2x0 C., and after transformation from the xe2x80x94SO2F form into the xe2x80x94SO3H form, as hereafter indicated.
The mechanical properties of the invention ionomers, for a TFE/(B) copolymer wherein q=2, are high, in particular there are the following mechanical properties of the film at 23xc2x0 C. at:
The fluorinated monomers of type (A) are selected from:
vinylidene fluoride (VDF);
C2-C8 perfluoroolefins, preferably tetrafluoroethylene (TFE);
chlorotrifluoroethylene (CTFE), optionally in the presence of ethylene,
(per)fluoroalkylvinylethers (PAVE) CF2xe2x95x90CFORf, wherein Rf is a C1-C6 (per)fluoroalkyl, for example trifluoromethyl, pentafluoropropyl;
perfluoro-oxyalkylvinylethers CF2xe2x95x90CFOX, wherein X is a C1-C12 perfluoro-oxyalkyl having one or more ether groups, for example perfluoro-2-propoxy-propyl.
Preferably (A) is TFE. Preferably (B) is the monomer with q=2.
Optionally the sulphonic fluorinated ionomers of the invention can contain from 0.01 to 5% by moles of monomeric units deriving from a bis-olefin of formula:
R1R2Cxe2x95x90CHxe2x80x94(CF2)m0xe2x80x94CHxe2x95x90CR5R6xe2x80x83xe2x80x83(I)
wherein:
m0=2-10, preferably 4-8;
R1, R2, R5, R6, equal to or different from each other, are H or C1-C5 alkyl groups. The introduction of the bis-olefin has the advantage to increase the length of the polymer chains.
Preferably the fluorinated sulphonic ionomers of the invention comprise:
monomeric units deriving from TFE;
monomeric units deriving from CF2xe2x95x90CFxe2x80x94Oxe2x80x94CF2CF2SO2F; optionally, monomeric units deriving from the bis-olefin of formula (I).
The invention ionomers can optionally contain I and/or Br atoms. It can be carried out by addition, in the reaction mixture, of brominated and/or iodinated xe2x80x9ccure-sitexe2x80x9d comonomers, such bromo and/or iodo olefins having from 2 to 10 carbon atoms (as described for example in U.S. Pat. Nos. 4,035,565 and 4,694,045), or iodo and/or bromo fluoro-alkylvinylethers (as described in U.S. Pat. Nos. 4,745,165, 4,564,662 and EP 199,138). The amount of said xe2x80x9ccure-sitexe2x80x9d is such that the content of xe2x80x9ccure-sitexe2x80x9d comonomers in the final product is generally in the range 0.05-2 moles per 100 moles of the other basis monomeric units. Alternatively or also in combination to the xe2x80x9ccure-sitexe2x80x9d comonomers, it is possible to introduce in the end groups iodine and/or bromine atoms by addition to the reaction mixture of iodinated and/or brominated chain transfer agents, such for example the compounds of formula Rf, (I)x(Br)y, wherein Rf, is a (per)fluoroalkyl or a (per)fluorochloroalkyl having from 1 to 8 carbon atoms, while x and y are integers comprised between 0 and 2, with 1xe2x89xa6x+yxe2x89xa62 (see for example U.S. Pat. Nos. 4,243,770 and 4,943,622).
Besides, inorganic or polymer fillers can preferably be added to the ionomer to further improve the membrane hydration at high temperatures. The filler amount is between 0 and 20% by weight with respect to the ionomer. Examples of fillers are zeolites, silicas, titanates, sulphoarylphosphonates of Zr, Ti, Hf in lamellar form, etc., acrylic polymers, etc. Fillers can also be used to improve the mechanical properties. They can be organic and/or inorganic, in particular among those inorganic, silica, celite, kaolin, etc, can be mentioned; among those organic polymers such 0fluorinated polymers PVdF, PCTPE, E/CTFE, E/TFE and thermoprocessable perfluorinated polymers, for example PFA, MFA or PTFE can be mentioned. PTFE, optionally containing perfluoro(alkoxy)vinylethers and/or HFP, is preferably used in nanoparticle form (ex. 10-80 xcexcm).
The sulphonic fluorinated ionomers of the invention can be used for the preparation of both self-supportd membranes and supported membranes. The membranes can be obtained for example by an extrusion process to obtain a film having the desired thickness. When the membranes are supported, as a support a fluorinated porous product, preferably perfluorinated, having the desired sizes and thicknesses, can be used, on which the ionomer is deposited.
The membranes of the invention are subjected to the activation treatment to transform the sulphonyl groups xe2x80x94SO2F into the sulphonic groups xe2x80x94SO3H. For example the activation can be carried out in 2 steps:
salification to transform the xe2x80x94SO2F form into the xe2x80x94SO3K form;
acidification to transform the xe2x80x94SO3K form into the xe2x80x94SO3H form.
For example the salification is carried out by dipping the membrane (film) in an aqueous solution containing 10% by weight of KOH at a temperature in the range 60xc2x0 C. -80xc2x0 C. for a time higher than 2 hours. At the salification end, the membrane is placed in a distilled water bath at room temperature to wash the residual KOH. The acidication is carried out for example by placing the salified membrane in an aqueous solution containing 20% by weight of HCl at room temperature for at least 2 hours, then a washing in demineralized water follows. The resulting membrane in the xe2x80x94SO3H form is suitable to be used in fuel cell applications.
As said the invention membranes are usable for the above uses, preferably in fuel cells, in particular for the automotive field.
The membranes obtainable from the invention sulphonic ionomers unexpectedly and surprisingly show an optimal combination of improved hydration and improved mechanical properties, as above mentioned. Besides the non supported membranes obtainable with the invention ionomers can be obtained with particularly thin thicknesses. The invention membrane thicknesses can preferably range from 5 xcexcm to 500 xcexcm, still more preferably from 10 to 250 xcexcm. Unsupported membranes having particularly thin thicknesses, for applications in the automotive industry, have a thickness from 20 to 60 xcexcm.
The membranes of the invention can be used in a wider temperature range, from room temperature up to 180xc2x0 C., preferably from 70xc2x0 C. to 120xc2x0 C.
The invention membranes maintain physical integrity even by operating at high temperatures, higher than 100xc2x0 C., even under conditions of unsaturation of the feeding fluids to the fuel cell.
For applications as fuel cell, the ionomers used for the membranes have EW preferably from 720 to 1,200 and more preferably from 750 to 1,100.
As said the invention ionomers are partially crystalline, i.e. they show at least a melting enthalpy peak at the DSC analysis (Differential Scanning Calorimetry).
The preparation of the invention sulphonic ionomers can be carried out by a radical polymerization process in bulk, suspension, emulsion wherein it is used a ratio:
[(B)/(A) in feeding]/[(B)/(A) in the polymer]
higher than 2.20, preferably higher than 2.50 for EW up to 800; said ratio being higher than 2.00, preferably higher than 2.20 for EW greater than 800.
The polymerization in aqueous emulsion or in microemulsion can for example be mentioned. Surfactants which can be used in said polymerizations are (per)fluorinated for example the salts (as defined hereunder) of the perfluorooctanoic, perfluorononanoic, perfluorodecanoic acid, or mixtures thereof, etc., (per)fluoropolyethers with an acid end group (for example xe2x80x94COOH, xe2x80x94SO3H), salified with NH4+, alkaline metals, the other end group being (per)fluorinated, optionally containing one H or Cl atom. The number average molecular weights of the perfluoropolyether surfactants generally range from 300 to 1,800, preferably from 350 to 750.
The polymerization in microemulsion is well known in the prior art.
In particular the preparation of the sulphonic ionomers object of the present invention is carried out by using an aqueous emulsion wherein in the reaction medium as surfactants those of formula:
Rfxe2x80x94Xxe2x88x92M+
are used, wherein
X is equal to xe2x80x94COO, xe2x80x94SO3;
M is selected from H, NH4, alkaline metal;
Rf represents a (per)fluoropolyether chain, preferably having number average molecular weight comprised between about 230 and about 1,800, preferably from 300 to 750, said (per)fluoropolyether chain comprising repeating units selected from one or more of the following:
a) xe2x80x94(C3F6O)xe2x80x94;
b) xe2x80x94(CF2CF2O)xe2x80x94;
c) xe2x80x94(CFL0O)xe2x80x94, wherein L0=xe2x80x94F, xe2x80x94CF3;
d) xe2x80x94CF2(CF2)zxe2x80x2CF2Oxe2x80x94, wherein zxe2x80x2 is an integer 1 or 2;
e) xe2x80x94CH2CF2CF2Oxe2x80x94.
Rf is monofunctional, and has a (per)fluorooxyalkyl end group T, for example CF3Oxe2x80x94, C2F5Oxe2x80x94, C3F7Oxe2x80x94; optionally in the perfluoroalkyl end groups one fluorine atom can be substituted by one chlorine or hydrogen atom. Examples of said end groups are Cl(C3F6O)xe2x80x94, H(C3F6O)xe2x80x94. The unit a) C3F6O is xe2x80x94CF2xe2x80x94CF(CF3)Oxe2x80x94 or xe2x80x94CF(CF3)CF2Oxe2x88x92.
In particular Rf has preferably one of the following structures:
Txe2x80x94(CF2O)axe2x80x94(CF2CF2O)bxe2x80x94CF2xe2x80x94xe2x80x83xe2x80x831)
with b/a comprised between 0.3 and 10, extremes included, a being an integer different from 0;
Txe2x80x94(CF2xe2x80x94(CF2)zxe2x80x2xe2x80x94CF2O)bxe2x80x2xe2x80x94CF2xe2x80x94xe2x80x83xe2x80x832)
wherein zxe2x80x2 is an integer equal to 1 or 2;
Txe2x80x94(C3F6O)rxe2x80x94(C2F4O)bxe2x80x94(CFL0O)txe2x80x94CF2xe2x80x94xe2x80x83xe2x80x833)
with r/b=0.5-2.0 (r+b)/t=10-30, b and t being integers different from 0 when all the units with indexes r, b, and t are present; or b=t=0, or b=0;
a, b, bxe2x80x2, r, t, are integers, whose sum is such that Rf has the above values of number average molecular weight.
The compounds wherein Rf has the following formula are still more preferred:
Txe2x80x94(CF2CF(CF3)O)m(CF2O)nxe2x80x94CF2xe2x80x94
wherein m/n=1-30;
wherein T=xe2x80x94OCF3 or xe2x80x94OCF2Cl,
X is a carboxylic group and M is NH4, K.
The (per)fluoropolyethers Rf are obtainable with the processes well known in the prior art, see for example the following patents herein incorporated by reference: U.S. Pat. Nos. 3,665,041, 2,242,218, 3,715,378, and the European patent EP 239,123. The functionalized fluoropolyethers with hydroxyl termination are obtained for example according to patents EP 148,482, U.S. Pat. No. 3,810,874, from which the functional groups X are obtained with the processes mentioned in said patents.
It is also possible to use in polymerization chain transfer agents. For example iodides and/or bromides of alkaline or alkaline-earth metals, according to U.S. Pat. No. 5,173,553. Preferably chain transfer agents containing hydrogen, such as hydrocarbons, alcohols, in particular ethyl acetate and ethane are used.
The polymerization initiators used in the process of the present invention are preferably radical inorganic initiators, such for example the ammonium and/or potassium and/or sodium persulphate, optionally in combination with ferrous, cupreous or silver salts. The procedures of the initiator feeding into the polymerization reactor can be in a continuous way or by a single addition at the polymerization starting.
The polymerization reaction is generally carried out at temperatures in the range 25xc2x0-70xc2x0 C., preferably 50xc2x0-60xc2x0 C., under a pressure up to 30 bar, preferably higher than 8.
The monomer (B) is fed into the polymerization reactor in a continuous way or by step.
When the polymerization is over, the ionomer is isolated by conventional methods, such as the coagulation by addition of electrolytes or by cooling.
The present invention will now be better illustrated by the following embodiment Examples, which have a merely indicative but not limitative purpose of the scope of the invention itself.

Abstract: and having the following properties for a TFE/(B) copolymer:

Abstract: hydration, expressed in % of H2O at 100xc2x0 C. absorbed by the film prepared from the ionomer and after tranformation from the xe2x80x94SO2F form into the xe2x80x94SO3H form, having the following values:


A process for forming a metal interconnection in an integrated circuit includes forming a first metal layer and a second metal layer on the first metal layer. Photoresist is placed on the second metal layer and patterned to form a mask. The second metal layer is etched. The mask is then removed and the first metal layer is patterned with the second metal layer acting as mask for the first metal layer.

1. Technical Field
The present disclosure relates to the field of integrated circuits. The present disclosure relates more particularly to integrated circuits in printers.
2. Description of the Related Art
Metal interconnections are a standard feature of integrated circuits. Integrated circuits typically include a monocrystalline semiconductor substrate on which transistors are formed. Source and drain regions of the transistors are formed in the semiconductor substrate and a gate electrode is formed above the semiconductor substrate. A series of metal layers are formed above the semiconductor substrate. Metal tracks are formed in each metal layer. The first metal layer is typically called metal 1 with the next metal layer above that being called metal 2 and so forth. The metal layers are patterned to form metal tracks. Vias are formed in the dielectric materials separating metal layers so that metal tracks from one metal layer can be electrically connected to metal tracks in a lower or higher metal layer. Contact vias are also made to contact the source drain and gate electrodes of the transistors to electrically connect them to the metal tracks.
In a typical metal interconnection, a metal track of a first metal layer is electrically connected to a metal track of a second metal layer. After the first metal track is formed, a dielectric material is deposited on the first metal layer. The dielectric layer is then etched in a selected location to open a via to the first metal layer. The second metal layer is then deposited, patterned, and etched to form metal tracks in the second metal layer. When second metal layer is deposited, the via is filled with the second metal which acts as a contact via to the metal tracks formed by the first metal layer. Typically a thin barrier layer, or an adhesion layer, will be deposited just prior to the deposition of the second metal layer. The barrier layer overlies the dielectric layer and lines the inner walls of the via formed in the dielectric layer. The barrier layer also contacts the exposed portion of the first metal layer. After the barrier layer has been deposited, the second metal layer is then deposited, entirely filling the rest of the via and forming a metal layer on top of the insulating layer. The metal layer and the barrier layer are subsequently patterned and etched to form the desired metal tracks and interconnections.
FIG. 1A illustrates a conventional metal interconnection 20. A first metal track 22 is formed of metal 1. The first metal track 22 is, for example, AlCu. A dielectric layer 24 is then formed on the first metal track 22. The dielectric layer 24 may include multiple layers including silicon dioxide, silicon nitride, phosphor-silicate glass, or spin-on glass. The dielectric layer 24 has been etched to expose a portion of the metal track 22. A Ta barrier layer, for example 500 Å thick, has been deposited on the dielectric layer 24 and covers the sidewalls of the dielectric layer 24 as well as the exposed portion of the first metal track 22. A second metal 28 layer is deposited on top of the Ta layer. The metal layer 28 is, for example, gold, and is 3.7 kÅ thick. A photoresist layer 30 has been formed on top of the metal layer 28. The photoresist layer 30 has been patterned to form a mask in the desired pattern of the metal tracks which will be formed of the metal layer 28 and the barrier layer 26.
In FIG. 1B, the second metal layer 28 has been subjected to an isotropic wet metal etch. The wet metal etch etches the gold layer 28 outside of the photoresist layer 30. Because an isotopic etch was used, a portion of the gold metal layer 28 was undercut below the photoresist to form an overhang.
In FIG. 1C the Ta layer 26 is also subjected to an isotropic wet metal etch. The Ta layer 26 is etched outside of the photoresist layer 30 and the gold layer 28. Because an isotopic etch was used, a small portion of the Ta layer 26 is also etched under the edge of the gold layer 28. In FIG. 1D, the photoresist layer 30 has been stripped away. After the photoresist layer 30 is stripped away, a spin dry process is performed to dry the integrated circuit.
As discussed above, the top metal layer 28 is typically made of gold because it does not corrode easily and adds excellent adherence properties to the photoresist layer so that the metal layers can be etched as a single stack with the photoresist present. Gold also has other benefits of being an excellent conductor of both electricity and heat. The gold can rapidly transfer heat away from the heater for the Ta layer 26 and can also provide good electrical coupling.
Unfortunately, gold has recently become extremely expensive, and with the rising gold prices it is desirable to use another metal besides gold for the upper layer 28. Unfortunately, simply substituting another metal layer for gold cannot easily be done and several difficulties are encountered if the current process is used and another metal is merely substituted in place of the gold layer 28.
The use of a Ta alloy, such as tantalum silicon oxide as a resistor in the heater section of an ink jet printer, is well known in the art and is described for example in U.S. Patent Publication 2005/0052501. In addition, the use of gold as a top metal layer as part of a nozzle for an ink jet printer is described in various issued U.S. patents and other patent publications including U.S. Pat. No. 7,881,594 and U.S. Patent Publication 2010/0163116. Any reference to Ta herein therefore includes alloys thereof and structures that can act as resistors.


A third party item listing management system usable for verification of third party items to be included on a retailer website includes an application programming interface and an item verification pipeline. The application programming interface is accessible by a plurality of third parties and is configured to receive item data associated with one or more items. The item verification pipeline is configured to receive the item data and call an item validation pipeline, the item validation pipeline includes a plurality of item validation stages including a field verification. At the field verification stage, data is extracted from at least one of an item image or text associated with the item. The data extracted is compared to item data obtained from an independent verification source to confirm the accuracy of the item data provided by the third party.

Retail enterprises, and in particular online retail enterprises, are increasingly supporting sales from third party sellers, e.g., through the retailer's website. This presents a number of challenges to the retailer. For example, customers who may have complaints regarding a particular item or who wish to return that item may be required to return that item to different suppliers, despite the customer purchasing the item from the retailer website in a manner that may not be obvious to the user that his/her order is fulfilled by a seller other than the retailer. Furthermore, because a number of sellers may be supported, it is possible that different sellers may wish to sell the same or similar items, or items from the same brand, or of the same type.
For online retail portals that operate as hosted platforms for reselling (e.g., eBay, Amazon, etc.,) presenting a customer with duplicate or similar items is less of a concern, since customers expect to be purchasing from third parties and can compare reviews of those third parties. However, in cases where an online retailer sells items from their own item collection alongside offerings from third parties, presentation of multiple similar items may cause customer confusion, and result in a degraded online experience.
Online retailers can also face challenges if a third party seller proposes to sell an item with incorrect, incomplete, or even offensive item information. If information provided by a third party is not verified, the incorrect or incomplete item information appears on the retail's website and can purport to be endorsed by the retailer, leading to a negative perception of the retailer by potential customers.

System for third party sellers in online retail environment