An encoding method comprises generating a character map of an alphanumeric character string, identifying runs of like character type symbols in sequential positions, and removing the runs of character type symbols from the character map. The center for the center infix run is determined, and the characters of each character type are encoded into binary encoded substrings. A decoding method comprises parsing the one or more run fields in the alphanumeric header to determine a number of characters of each type of a plurality of character types represented in the binary encoded string, generating a character map having a string of character type symbols representing the binary encoded string, including determining a reduced character map, centering the character type symbols for a center infix run about the center of the reduced character map, completing a final character map, and decoding each binary encoded string.

1.0 Radio Frequency Identification (RFID) Tags
Radio frequency identification (RFID) tags are electronic devices that may be affixed to items whose presence is to be detected and/or monitored. A variety of tag classes have been defined by national and international standards bodies (e.g., EPCGlobal and ISO). The tag classes include Class 0, Class 1, and Class 1 Generation 2 ("Gen 2"). The presence of an RFID tag, and therefore the presence of the item to which the tag is affixed, may be checked and monitored wirelessly by devices known as "readers." Readers typically have one or more antennas transmitting radio frequency signals to which tags respond. Because the reader "interrogates" RFID tags, and receives signals back from the tags in response to the interrogation, the reader is sometimes termed as "reader interrogator" or simply "interrogator."
With the maturation of RFID technology, efficient communication between tags and interrogators has become a key enabler in supply chain management, especially in manufacturing, shipping, and retail industries, as well as in building security installations, healthcare facilities, libraries, airports, warehouses etc.
In addition, tags include limited amounts of memory for encoding user data. Existing standard data formats (e.g., as specified by ISO/IEC 15961 and 15962) do not offer good compaction efficiency, nor do they offer fast random access to a desired data element. In addition, Gen 2 standards limit the data systems which can be used to label data items. This limits the ability of users of Gen 2 tags to encode data items. Some users may desire to use GS1 Application Identifiers (AIs), whereas others may want to use Data Identifiers (DIs), and others may want to intermix the two. Furthermore, the Gen 2 air interface protocol does not provide a good mechanism for accessing a variable amount of memory, without requiring multiple operations of the same tag. In current Gen 2 implementations, the only options are (1) read the entire memory bank, which may entail reading a very large number of useless '0' bits thus slowing down the process for reading a population of tags, or (2) read a selected number of memory words. The problem with alternative (2) is that if too many words are requested, the tag returns an error code with no indication of how many words were actually available.
2.0 Optical Media
Optical media such as bar codes are machine readable representations of information, often dark ink on a light background that creates high and low reflectance which can be converted to a digital format. Barcodes may represent or encode data by the widths and spacings of printed parallel lines, patterns of dots, concentric circles, and text codes hidden within images. Barcodes are often read by optical scanners called barcode readers or scanned from an image by special software.
Barcodes are widely used to implement Auto ID Data Capture (AIDC) systems that improve the speed and accuracy of computer data entry. Barcodes are typically extremely accurate and inexpensive. However, the amount and type of data that can be encoded in a bar code is limited.
The drive to encode more information in combination with the space requirements of simple barcodes led to the development advanced bar codes such as stacked barcodes and 2D barcodes. For example, matrix codes, a type of 2D barcode, do not consist of bars but rather a grid of square cells. Stacked barcodes are a compromise between true 2D barcodes and linear codes (also known as 1D barcodes), and are formed by taking a traditional linear symbology and placing it in an envelope that allows multiple rows.
3.0 Optimizing Data Encodation
Many media, such as high capacity optical media (such as 2D bar codes) and RFID tags (such as EPCglobal Gen 2 tags), share a need for optimizing the encodation of the data sets typically used in AIDC applications.
For example, existing standard RFID formats (e.g., ISO/EIC 15961 and 15962) and barcode encodation methods (e.g., Data Matrix, ISO/IEC 16022) do not offer good compaction efficiency or fast random access to a desired data element. In optical-media applications, available "real estate" for the optical mark is usually the motivating factor for improving encoding efficiency. In the case of RFID applications, on the other hand, there are two prime motivators: the need to fit the data within a fixed and limited amount of Read/Write memory on a particular tag, and the need to minimize the number of data bits that must be transferred over the relatively-slow air interface.
A particularly-important metric for evaluating encoding schemes for AIDC applications is the worst-case number of bits needed to encode data fitting specific application rules and typical usage. For example, two of the most common AIDC data sets are a GS1 Lot Number (Application Identifier 10) and a GS1 Serial Number (A.I. 21). Both of these are defined to use up to 20 Alphanumeric characters from the 82-member character set defined in ISO/IEC 646. However, in actual use, most applications define their Lot and Serial Numbers to contain only digits and capital letters. Therefore, optimized AIDC encoding methods need to address both the absolute worst case (a 20-character data string using full ISO/IEC character set), and the typical worst case (a 20-character string using only digits and capital letters).
Until recently, the available encodation schemes were far from optimal for real-world AIDC data, especially for the typical worst case scenario. To address this need to minimize the number of encoded bits, a multi-base encodation scheme was developed. For example, see the detailed discussion of Packed Objects in U.S. Pat. No. 6,196,466, filed Jun. 9, 1999, entitled "Data Compression Method Using Multiple Base Number Systems" (hereinafter the '466 patent); U.S. patent application Ser. No. 11/806,050, filed May 29, 2007, entitled "Data Format for Efficient Encoding and Access of Multiple Data Items in RFID Tags" (hereinafter the '050 application); and U.S. patent application Ser. No. 11/806,053, filed May 29, 2007, entitled "Data Format for Efficient Encoding and Access of Multiple Data Items in RFID Tags" (hereinafter the '053 application), each of which are incorporated by reference herein in its entirety.
To further address the need to minimize the number of bits to be transmitted over an interface, multi-base encodation within an overall encoding format and structure can be used to provide many encodation efficiencies for known-numeric data (such as for GS1's A.I. 00) and additional transmission efficiencies. Examples of these techniques are described in the '050 and the '053 applications.
Packed Objects are one of the techniques to improve the efficiency of encoding, transmission and decoding. Packed Objects, as described in the above references, allow a receiving system to examine only the initial bits of a set of encoded data items to determine whether a data set of interest is present instead of reading all the bits in search of the data item. Thus, when reading large numbers of tags (some without the data item of interest) in search of a data item, the average number of transmitted bits is reduced.
The encoding efficiency of a AlphaNumeric (A/N) section of a Packed Object, based on multi-base encoding is provides significant improvements over traditional AIDC encoding methods for their worst-case scenario, which is a random mix of letters and numbers. These traditional methods classify input characters into a number of subsets (such as for digits and for uppercase letters), where these subsets need to include numerous "switches" and "latches" to alternate subsets, which reduces encoding efficiency in two ways. First, these non-data switches and latches increase the number of members needed in each subset (which increases the number of information bits needed to represent the data characters of the sub, thus reduces the encoding efficiency of the subset). Second, these traditional switches and latches require the same number of encoded bits as do the data characters of the starting subset, thus, for example, it costs five bits to latch out of a five-bit subset (for letters) to a four-bit subset (for digits), and another four bits to latch back from digits to letters.
Further, traditional AIDC methods define one or more sets of fixed-size output patterns, which in the case of optical media, use an integral number of bars and spaces, or in the case of bitstream-encoded media such as RFID tags, use an integral number of bits for each defined output character or defined grouping of two or three output characters. Since each output pattern, character, or group represents a non-integral number of abstract information bits, efficiency is reduced by integral representations of the data. For example, each digit of a set of decimal (base 10) digits represents 3.3219 (ln 10/ln 2) bits of information. When conveying decimal digits in a four-bit output grouping, for example, only 83 percent efficiency is achieved.
Multi-base encoding is not restricted to integral numbers of output bits, and does not rely on encoding switches and latches in order to mix digits and letters. Therefore the worst-case encoding efficiency of multi-base encoding is superior to traditional AIDC methods.
"Code 5" encoding is currently an active proposal in the AIDC community. It defines output character sets of 4, 5, 6, 7, and 8 bits, plus predefined output groupings such as 3 digits in 10 bits, and each set contains numerous switches and latches to the other Code 5 set.
Because of the high cost of traditional switches and latches, the most efficient way to encode mixed letters and digits in Code 5 (such as the data string "A12B34C56") is to use Code 5's six-bit code set for the entire string. Including four bits of overhead to latch into the six-bit code set, plus six bits to individually represent each of the nine data characters, this string requires a total of 58 bits to encode in Code 5 (averaging 6.44 bits per character). In contrast, the A/N encoding used in the Packed Objects specification requires only 48 bits (averaging 5.33 bits per character): four bits of overhead to define the particular characteristics of this instance of multi-base encoding, a 9 bit character map (e.g., "100100100") where each '1' or '0' indicates the positions of an individual letter or digit (respectively) within the data string, 20 bits to encode the six digits of the string (converted to a single base 256 value), and 15 bits to encode the three uppercase letters of the string (converted to a single base 256 value).
In general, the worst-case mixes of digits and uppercase letters in Code 5 all require an incremental cost (i.e., the average cost to encode another character) of 6.0 bits per character, excluding start-up overhead, which becomes less significant for longer source messages. Using multi-base encoding, the worst case mixes of digits and uppercase letters require only 5.11 bits per character, excluding start-up overhead.
Worst-case metrics are of particular importance to users because they answer the question of whether a user's data sets will always fit in the available storage (e.g., in a bar code format or the RFID memory). The metrics for average encodation efficiency are also of interest. Accepted industry statistics for the distributions of alphanumeric string contents (the typical mix and sequence of letters and digits) do not exist, however, so one currently cannot predict true "average" performance of an AIDC encodation method in the field.
For some particular mixes and sequences of messages, pure multi-base encoding may be less efficient than traditional methods, unless the multi-base encoding is augmented with additional techniques. An all-numeric message will have an incremental cost of 4.32 bits per character under multi-base encoding versus four bits for a method that can latch to a four-bit character set. For example, the Packed Objects structure allows many important data fields known in advance to be all-numeric to be encoded without a character map, thus achieving an incremental cost of only 3.32 bits per character—the optimal encoding for digits according to information theory.
Also, the header structure for the A/N section in a Packed Objects allows optional definition of a Prefix, Suffix, or Infix, in which the character map can be omitted for long substrings of characters from the same numeric base. Instead of encoding that portion of the character map, that portion (of all '0's or all '1's) is run-length encoded. Note that unlike traditional run-length encoding schemes, which provide a compacted representation of a string of identical data characters, or classes of data bit patterns, the run length in a Packed Object provides a compacted representation of the character map, not of the data content. Also, the Prefix/Suffix/Infix mechanism is different from and superior to traditional latching and shifting mechanisms.
Latches and shifts need to be a defined part of the current character set in order to be invoked from that set. Consequently, the shift/latch facility adds to the size of each character set, and therefore reduces the encoding efficiency of every character set in the scheme, even if never invoked for a given data set. In contrast, the Prefix/Infix/Suffix mechanism is defined outside of the character sets and is not encoded as part of any character set, and thus has no negative incremental efficiency penalty unless invoked.
Although such additional techniques do provide significant additional encoding efficiencies, the Prefix/Infix/Suffix mechanism used in Packed Objects is somewhat limited in the percentage of data mixes in which it is most useful. For example, if the first four characters of a data string include both letters and digits, then a Prefix cannot be used. As another example, the Infix mechanism includes a pointer to the starting position of the Infix within the data stream, which costs several additional overhead bits. Thus, the Infix mechanism is most beneficial when the data has particularly long runs of the same base. Finally, because Prefix/Infix/Suffix must contain either only digits or only non-digits, many data strings cannot use the Prefix and/or Suffix at all (because the string starts and/or ends with mixed characters), and the length of the allowable Prefix, Suffix, or Infix rarely constitutes a significant percentage of a large message due to the odds that at least one character would occur that would interrupt the single-base run.
Thus, what is needed is a system and method for encoding A/N and other mixed data strings when data strings contain substrings that are primarily, but not exclusively, from a single character class. Further, what is needed is an enhanced Prefix/Infix/Suffix mechanism to better handle mixed data sets and longer data sets. Moreover, what is needed are new methods and systems to flexibly mix ID tables of different sizes for different data systems in Packed Objects to help maintain backward compatibility.

Efficient encoding and decoding of mixed data strings in RFID tags and other media


The present invention aims to provide a novel undifferentiated state-control agent that maintains and/or improves an undifferentiated state of undifferentiated cells. CCL2 or a protein containing a functional domain thereof is used as the undifferentiated state-control agent. By culturing undifferentiated cells in the presence of the control agent, it is possible to maintain and/or improve an undifferentiated state of the undifferentiated cells. Examples of the undifferentiated cells include embryonic stem cells (ES cells) and induced pluripotent stem cells (iPS cells). The origin of the cells is not particularly limited, and may be a human, mouse, or the like, for example.

Cells having pluripotency, such as ES cells and iPS cells, are undifferentiated cells. Owing to the pluripotency of the undifferentiated cells, the applicability of the undifferentiated cells to regenerative medicine etc. is attracting attention, and research and development regarding the undifferentiated cells now are being carried out eagerly. To this end, it is important to maintain the undifferentiated state of the undifferentiated cells during their culture.
Generally, the undifferentiated cells are cultured according to a culture method using feeder cells such as fibroblasts (so-called "on-feeder culture method"). In this method, feeder cells are cultured beforehand, and undifferentiated cells are then seeded on the feeder cells. Also, in recent years, a culture method without involving the use of feeder cells is developed, which is a so-called "feeder free culture method". In the feeder free culture method, a serum-free medium is used, for example (Patent Documents 1 to 5, Non-Patent Documents 1 to 14).
However, these known culture methods cannot maintain the pluripotency and the undifferentiated state of the undifferentiated cells sufficiently. For example, in the case of mouse-derived pluripotent stem cells, LIF (Leukemia Inhibitory Factor) is added to a medium as a differentiation inhibitory factor. However, sufficient maintenance of the pluripotency and the undifferentiated state cannot be realized merely by adding LIF. Moreover, for human-derived pluripotent stem cells, effective means for maintaining and/or improving the pluripotency and the undifferentiated state thereof have not been established yet.

Control agent for controlling undifferentiated state and use thereof


The input stage of the fully differential amplifier output stage is configured in a differential pair configuration with a tail current. The tail current is divided between two legs of the input stage and is higher in the leg that has the higher of the two input voltage levels (in or inb). The devices in each leg of the fully differential amplifier output stage may be cascoded to avoid electrical voltage overstress. The top device in each leg of the differential input stage may be coupled in a diode configuration and is utilized to mirror the current into another NMOS current mirror as well as to a PMOS output device. The gate of the PMOS output devices are connected in a cross-coupled configuration. The NMOS current mirrors are utilized to mirror the current into the NMOS output devices in a non-cross-coupled configuration.

A transistor is an electronic device that permits current flow in electronic circuits. In this regard, the transistor permits the current to flow in a controlled manner whenever an electronic circuit attempts to push current through the transistor. In this manner, the transistor generically operates as a regulator or valve, which regulates the flow of current.
In order to mitigate the effects of impairments such as noise, transistors may be arranged so that they form a differential amplifier. Differential amplifiers form the basis of operational amplifiers, the latter of which are generally referred to as op amps. Differential amplifiers are electronic circuits, which are designed with an internal symmetry that is configured to cancel errors that are shared by both sides of the differential amplifier. These errors may include internal or external errors. Internal errors may include temperature changes, which in certain instances may affect both sides of the operational amplifier to approximately the same degree. Transistor mismatch is another example of an internal error. Whenever both sides are affected to approximately the same degree, a nulling or canceling effect occurs. External errors may include noise picked up by inputs of the differential amplifier. In this regard, the differential amplifier may be adapted to eliminate common mode noise. Furthermore, the differential amplifier may require that the signal appear as a difference between waveforms occurring on either side of the differential amplifier. Accordingly, the differential amplifier may be configured to reject certain signal components such as noise and amplify desired signal components.
Some conventional differential amplifiers require a reference voltage or reference current in order for the differential amplifier to operate properly. Additionally, some differential amplifier designs utilize large numbers of transistors. In general, the greater the number of transistor devices, the greater the number of operating variables that will vary with respect to each of the sides of a differential amplifier. Consequently, differential amplifiers that utilize a large number of transistors may be more difficult to control and tune, and may also be less predictable with respect to process or operating variations. Furthermore, most conventional analog differential amplifiers are generally adapted to take a relatively small differential input voltage and produce as an output a voltage having a larger magnitude. These conventional analog differential amplifiers are usually optimized to operate in a specified voltage range and may not function at all if operated outside that range.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with some aspects of the present invention as set forth in the remainder of the present application with reference to the drawings.

Method and apparatus for a fully differential amplifier output stage


By resolving objections in the prior art, provided are a novel copolymer suitable as a coating polymers which is excellent in adhesion to a substrate and can be used suitably as the polymer for the coating film having durability against pattern collapse in the finer pattern formation for progressed lithography technology and a method for producing the copolymer, as well as a novel thiol compound useful as a chain transfer agent in the production of the copolymer. The novel thiol compound of the present invention has the structure represented by the formula (1);

1. Field of the Invention
The present invention relates to a novel thiol compound useful as a chain transfer agent, a copolymer in radical copolymerization using the thiol compound as the chain transfer agent, and methods for producing the same. More particularly, the present invention relates to the copolymer suitably used for coating film in lithography such as resist film and anti-reflective coating, and the method for producing the same, as well as the novel thiol compound useful as the chain transfer agent in the production of the copolymer.
2. Description of Related Art
In semiconductor lithography, the formation of finer patterns has been required in conjunction with increase of integration degree. It is essential for micropatterning techniques to make a wavelength of irradiation light source shorter. Currently, the lithography by krypton fluoride (KrF) excimer laser (wavelength 248 nm) has become a mainstream, and the micropatterning techniques of 100 nm linewidth or less by argon fluoride (ArF) excimer laser (wavelength 193 nm) is coming into practical use. The micropatterning techniques using fluorine dimer (F2) excimer laser (wavelength 157 nm), extreme-ultraviolet ray (EUV), X-ray, electron beam, and the like are in developmental stages.
The resist polymer used for these lithography technologies has essentially a repeating unit having a non-polar substitute which is decomposed by an acid and becomes soluble in an alkali developer and a repeating unit having a polar group to enhance adhesion to a substrate. And if necessary, the resist polymer is comprising a repeating unit having non-polar substitutes to regulate solubility in a resist solvent or the alkali developer. As these repeating units, for example, in the KrF lithography, hydroxystyrenes and derivatives thereof have been primarily used, and in the ArF lithography, (meth) acrylates and derivatives thereof and the like have been considered because the hydroxystyrenes absorb the light with a wavelength of 193 nm.
As specific examples of such resist polymers, copolymers of (meth) acrylic monomer with styrene type monomer (see e.g., Patent References 1 to 4), polymers containing hydroxystyrene which is partially protected with acetal (see e.g., Patent References 5 to 8) and the like are known in the KrF lithography, and copolymers of (meth)acrylic monomer having lactone structure (see e.g., Patent references 9 to 10) are known in the ArF lithography.
Whereas, even in the polymer comprising the repeating unit having the polar group to enhance the adhesion to the substrate as the above, it is a problem that finer patterns cannot be achieved because end-groups of the polymer derived from a initiator or a chain transfer agent used at the polymerization don't have sufficient adhesion property.
Also, in the resist pattern formation, it is a problem that resist patterns collapse due to surface tension of the washing water vaporizing in a drying process after development and rinsing. Especially, the pattern collapse occurs easily because a pattern-substrate contacting area becomes small when the pattern becomes finer. To avoid this, it is necessary to keep an aspect ratio (height/width) low, but on the other hand, it is required to make a coating film thick in order to satisfy dry etching resistance of the pattern, that is, to make the aspect ratio of the resist pattern high. Thus, the resist polymer with higher adhesion to the substrate where the aspect ratio can be increased and the pattern collapse does not occur even in fine pattern formation has been needed.
Thus, the several methods using a polymerization initiator and a chain transfer agent having a polar group have been studied to enhance adhesion of the resist polymer to the substrate. As an example using the polymerization initiator having a polar group, the method using the polymerization initiator having an oxygen-containing group or a substituted or unsubstituted amino group in the molecule is known (see e.g., Patent Reference 11). In the reference, hydroxyl group, carboxyl group, substituted oxyl group, substituted oxycarbonyl group, acyl group, substituted or unsubstituted carbamoyl group, hydroxyimino group, and substituted or unsubstituted oxyimino group are disclosed as the oxygen-containing groups. However, in the method of using carboxyl group, it has been a problem that swelling occurs easily in the alkali developing process after the exposure because of the strong hydrophilic property of carboxyl group, and then no stable pattern is obtained in finer lithography even if the alkali-solubility and the substrate adhesion can be improved. In the method of using hydroxyl group, substituted oxyl group, substituted oxycarbonyl group, acyl group and the like, it is insufficient to improve the adhesion to the substrate, because the polarity of these groups is weak. Furthermore, the method of using the oxygen-containing group comprising nitrogen atoms such as substituted or unsubstituted carbamoyl group, hydroxyimino group or substituted or unsubstituted oxyimino group or the like, and the method of using the substituted or unsubstituted amino group are not practical, because these nitrogen-containing groups trap the acid generated from acid generator and make sensitivity lower.
At the same time, as examples using the chain transfer agent having the polar group, the method of using carboxyl group-containing thiol such as mercaptoacetic acid and mercaptopropionic acid as the chain transfer agent (see e.g., Patent Reference 12) and the method of using ester compounds thereof or hydroxyl group-containing thiol such as mercaptoethanol are known (see e.g., Patent Reference 13 to 14). However, also in these methods, as with the case of the above polymerization initiator, it is a problem that the swelling easily occurs at the alkali development in the method of using carboxyl group-containing thiol, and the adhesion to the substrate is insufficient in the method of using the ester compound or hydroxyl group-containing thiol, and both cannot reach to practical levels.
Moreover, in the lithography on a high reflective substrate, it is difficult to trace fine resist patterns due to halation of reflected lights. To solve this issue, an anti-reflective coating polymer is coated under a resist coating film and absorbs the reflected lights of the substrate. Furthermore, in the multi-layer resist application for progressed lithography technology, a bottom layer coating polymer is coated under the thin resist coating film and imaged by dry etching. For all these coating, polymers, the adhesion to the substrate is important, and more excellent adhesion is required.                Patent Reference 1                    JP-A-59-45439                        Patent Reference 2                    JP-A-5-113667                        Patent Reference 3                    JP-A-7-209868                        Patent Reference 4                    JP-A-11-65120                        Patent Reference 5                    JP-A-62-115440                        Patent Reference 6                    JP-A-4-219757                        Patent Reference 7                    JP-A-3-223860                        Patent Reference 8                    JP-A-4-104251                        Patent Reference 9                    JP-A-9-73173                        Patent Reference 10                    JP-A-10-239846                        Patent Reference 11                    JP-A-2002-20424                        Patent Reference 12                    JP-A-10-55069                        Patent Reference 13                    JP-A-2000-19737                        Patent Reference 14                    JP-A-2001-117231

Thiol compound, copolymer and method for producing the copolymer

Abstract: wherein R1 is a bivalent substituent selected from linear, branched or cyclic saturated hydrocarbon having 1 to 15 carbon atoms.


The fractal image compression device of the present invention contemplates a control unit for dividing a composite image into a plurality of range blocks and a plurality of domain blocks, classifying the range blocks and domain blocks into several classes according to their respective attributes, and controlling an overall operation of the device. A page memory stores image data received from an external source, and provides output of the image data via control of the control unit. A domain block memory receives first pixel data within the domain blocks from the page memory, and stores the first pixel data via control of the control unit. A range block memory receives second pixel data within the range blocks from the page memory, and stores the second pixel data via control of the control unit. A slope and offset detecting unit spacially-transforms the first pixel data within the domain blocks to correspond one-to-one with corresponding second pixel data within the range blocks, calculates slope and offset values of contractive compression functions corresponding to the spacially-transformed domain blocks and the range blocks, calculates background sensitivities and edge sensitivities from the second pixel data within the range blocks, and calculates and provides output of distortion errors by multiplying brightness differences between corresponding pixels within the spacially-transformed domain blocks and the range blocks by the background sensitivities and the edge sensitivities. An image compression memory stores, as compression data, locations and the slope and offset values corresponding to ones of the domain blocks having minimum distortion errors, via control of the control unit.

The present invention relates to an image compression device and method, and more particularly, to a fractal image compression device and method using a contractive transformation function.
Digital image compression methods can be generally classified into transformation coding methods and vector quantization methods. With transformation coding methods (e.g., Joint Photographers Expert Group (JPEG) standard), image data is transformed into another domain, and compressed in the transformed domain. With vector quantization methods, a portion of image data is compared with images of a predetermined code book, and an index of the most similar code book image is then transmitted, thereby having a compression effect on the image data. Fractal image compression methods, as compared to the existing compression methods, approximate large quantities of digital image data by using a simple mathematical model, thereby having a compression effect on the image data.
With fractal image compression theory, one assumes that the image to be compressed is a fractal image having the property of self-similarity as the spatial scale is changed over several orders of magnitude. The property of self-similarity can be seen with, for example, a rocky, jagged coastline which looks similar when seen from a jet airplane (a distance of 10 km), from a low altitude plane (100 m) and from a standing position (1 m). Accordingly, for purposes of image processing, a contractive transformation function using the fractal image as an attractor can be obtained, thus compressing the image. It is very difficult, however, to obtain the contractive transformation function using the entire image to be compressed as the attractor. To resolve this problem with the fractal image compression method, the entire image is divided into a plurality of non-overlapping range blocks, and further divided into a plurality of domain blocks each having a size that is an integer (e.g., four) times larger than the size of each of the range blocks. The contractive transformation function for each one of the divided range blocks is obtained by contractively transforming the domain blocks into each of the range blocks, and calculating the errors between the contractively-transformed domain blocks and each of the range blocks. The domain block having a minimum error value for each range block is referred to as a matching domain block.
Jacquin's method is typically known as the most representative fractal image compression method based upon the method described above. In order to reduce the compression period, Jacquin's method classifies range blocks and domain blocks into several classes according to their attributes, and then, only the domain blocks belonging to the same class as a corresponding range block to be compressed are evaluated.
The fractal image compression method, which is theoretically capable of a very high-level of compression (i.e., 1/10,000), is an unsymmetrical process having a much shorter recovery period than compression period. Therefore, there is an advantage in that the fractal image compression method is useful in applications where high-speed image recovery is required.
Currently, an iterated function system (IFS) proposed by Barnsley et al. is being utilized as a fractal image compression device and method. This system is disclosed in detail in U.S. Pat. No. 5,347,600 entitled Method And Apparatus For Compression And Decompression Of Digital Image Data. The distortion measurement, which is used as a reference for determining the self-similarity characteristic between blocks in conventional fractal image compression devices and methods, is generally a mean square error (MSE). That is, the domain block having the minimum mean square error for a corresponding range block is determined to be the domain block having the best self-similarity characteristics. With many improved techniques for fractal image compression, the mean square error has been used for the distortion measurement between image blocks.
The similarity between image blocks and overall image quality, however, is ultimately determined by the perceptions of the human eye. In this context, use of the mean square error (MSE) has often presented problems in other image compression fields. Therefore, with conventional fractal image compression techniques, since the mean square error (MSE) does not always adequately reflect human visual properties, domain blocks that fail to provide "self-similarity" from a visual standpoint are often determined to be matching domain blocks. Accordingly, the quality of a recovered image may be numerically improved, but is visually deteriorated. Moreover, conventional fractal image compression techniques often provide a reduced compression rate due to unnecessary division of range blocks.

Fractal image compression device and method using perceptual distortion measurement


A method for adapting threshold values in an electronic signal processing device, involving a plurality of different threshold values being calculated and being compared with processing variables calculated in the signal processing device, involves calculation of a common correction value which is valid for the various threshold values. The threshold values are then set on the basis of the common correction value.

Threshold values are used for signal detection and for decision processes in a multiplicity of signal processing devices. By way of example, the signal power or a processing variable derived therefrom is tested against a prescribed value—the threshold value. Depending on whether the processing variable exceeds the threshold value, a signal is considered to have been detected or a particular decision is made.
By way of example, a threshold value decision can be used to test whether a received signal contains useful data. Normally, these useful data have superimposed disturbances (noise, interference) and need to be separated from these disturbances. By way of example, the received signal is processed in suitable fashion in a radio receiver (e.g., using a correlator) and the processing value is compared with a threshold value. If the processing value exceeds this threshold value, the useful signal is considered to have been detected. Otherwise, it is assumed that the received signal contains exclusively disturbance components.
A considerable drawback of threshold-value-based decisions is the dependency of the decision quality on the average received signal power, since absolute values are compared with one another. The received signal power may fluctuate considerably, however, for example as a result of switching by amplifier stages connected upstream. It thus becomes necessary to adapt the threshold values to the average power of the signal that is to be processed or to be tested.
FIG. 1 shows the normal approach of a signal processing device based on threshold value decisions. An input signal s is subjected to various signal processing procedures in various signal processing stages 1, 2, . . . , N. The respective signal processing stages have detectors 1.1, 2.1, . . . , N.1 connected downstream of them which test the processing signal which is output by the respective signal processing stage 1, 2, . . . N. The test is performed by comparing the processing signal with a respective threshold value. The respective threshold value is made available to the detector 1.1, 2.1, . . . , N.1 by a local threshold value generation stage 1.2, 2.2, . . . , N.2. For the requisite threshold value adaptation, local threshold value adaptation stages 1.3, 2.3, . . . , N.3 are provided which accept the respective processing signal at their input and make a correction value available at their output. The threshold-value-based correction value is supplied to the respective downstream threshold value generation stage 1.2, 2.2, . . . , N.2 via an interface. A result processing section connected downstream of the detectors 1.1, 2.1, . . . , N.1 evaluates the threshold value comparison results obtained from the detectors, manages them and then stipulates the further signal processing.
The local threshold value adaptation shown in FIG. 1 works perfectly in terms of function, but has the drawback that calculation of the adaptation values which are output by the threshold value adaptation stages 1.3, 2.3, . . . , N.3 requires a high level of involvement overall. Although the processing signals which are output by the signal processing stages 1, 2, . . . N are normally different, the usually very complex calculations of the adaptation values in the system are performed a plurality of times at least for some of the computation cycles. This firstly increases the circuit's power consumption and secondly results in an increased surface area requirement for the circuit on account of the high level of circuit complexity.

Method and apparatus for adapting threshold values in electronic signal processing devices


A method and system for controlling timing in a processor is disclosed. In one aspect of the present invention, the method comprises fetching a plurality of instructions, wherein each instruction has a first default execution time during a first condition, and wherein each instruction has a second default execution time during a second condition; during a first mode, executing the plurality of instructions within a same execution time regardless of whether a condition is the first condition or the second condition; and during a second mode, executing the plurality of instructions within random execution time regardless of whether a condition is the first condition or the second condition. According to the system and method disclosed herein, the method effectively modifies the timing of a processor by controlling and/or minimizing variations in the execution times of instructions.

A central processing unit (CPU) is the part of a computer that interprets and carries out instructions contained in software, which can have various functions such as controlling hardware, performing computations, and communication with other software. The timing execution of instructions may vary, depending on a number of various conditions (e.g., status register contents, the value of a bit, the size of the following instructions, accessed peripherals, etc.).
Variations in timing execution can be a serious problem when the timing must be constant or predictable. For example, during software communication routines, a co-processor must be synchronized with the CPU. Timing variations can also cause problems such as the leakage of sensitive information, etc.
Generally, known solutions are unreliable and time consuming to implement. For example, software routines are developed and manually balanced in Assembly Language to ensure that all possible paths execute in an equal number of clock cycles. This is an error prone and time-consuming process that also induces high maintenance costs and risks.
Accordingly, what is needed is an improved method and system for controlling timing in a CPU. The present invention addresses such a need.

Method and system having instructions with different execution times in different modes, including a selected execution time different from default execution times in a first mode and a random execution time in a second mode


A plate-shaped composite material has a first member and a second member. The first member is an expanded metal formed of a metal plate. The coefficient of linear expansion of the metal plate is less than or equal to 8×10−6/degrees Celsius. The first member suppresses thermal expansion of the composite material. The coefficient of thermal conductivity of the second member is greater than or equal to 200 W/(m×K). The second member maintains the coefficient of thermal conductivity of the composite material. This structure provides a reliable coefficient of thermal conductivity and high strength. The structure is suitable for a cooling substrate on which electronic elements such as semiconductors are mounted.

The present invention relates to a composite material and a manufacturing method of the composite material. More specifically, the present invention pertains to a composite material that is suitable for a cooling substrate on which electronic elements, such as semiconductors, are mounted, or a composite material that is suitable for wiring material of semiconductors. The present invention also pertains to manufacturing methods of the composite materials.
Typical electronic elements such as semiconductors generate heat when supplied with electric current. The electronic elements are cooled to prevent the performance from deteriorating.
Packaging methods of a semiconductor include the use of a heat sink. FIG. 16 shows an aluminum base 41, which constitute a casing, and a heat sink 42, which is secured to the aluminum base 41 by screws (not shown) or by soldering. An insulated-substrate 43 is secured to the heat sink 42 by soldering. The insulated-substrate 43 has metal (A1) layers 43a on both sides. An electronic element 44, such as a semiconductor, is mounted on one of the metal layers 43a of the insulated-substrate 43 by soldering. The insulated-substrate 43 is made of aluminum nitride (AlN). The heat sink 42 uses material having low coefficient of thermal expansion and high coefficient of thermal conductivity. The material may be metal matrix composite material having a metal matrix phase to which ceramics are dispersed. The metal matrix composite material may be, for example, an aluminum substrate to which silicon carbide (Sic) particles are dispersed.
The metal matrix composite material used for the heat sink 42 is expensive and has low workability. Therefore, a different cooling substrate that is inexpensive and has high workability has been proposed. For example, Japanese Laid-Open Patent Publication No. 6-77365 discloses a cooling substrate 47, which is integrally formed with metal plates 46 and a wire fabric 45 as shown in FIGS. 17(a) and 17(b). The metal plates 46 are made of copper, copper and tungsten, or copper and molybdenum. The wire fabric 45 is woven with thin metal wires made of molybdenum or tungsten. The metal plates 46 are laid on one another with the wire fabric 45 arranged in between. In this state, the metal plates 46 and the wire fabric 45 are heated and rolled. This integrates the metal plates 46 and the wire fabric 45 and forms a laminated sheet of the cooling substrate 47.
Japanese Laid-Open Patent Publication No. 7-249717 discloses a cooling substrate that is formed by integrating a wire fabric made of thin metal wires of molybdenum or tungsten with impregnant containing copper, copper and tungsten, or copper and molybdenum.
Japanese Laid-Open Patent Publication No. 6-334074 discloses a substrate for semiconductors as shown in FIG. 18. The substrate includes a base material 48, in which holes 48a are formed. The base material 48 is made of metal or alloy, the coefficient of thermal expansion of which is less than or equal to 8×10−6/degrees Celsius. The holes 48a are filled with highly thermal conductive material made of metal or alloy, the coefficient of thermal conductivity of which is greater than or equal to 210 W/(m×K). The highly thermal conductive material may be Cu, Al, Ag, Au or an alloy that mainly includes Cu, Al, Ag, or Au. The base material 48 may be an invar alloy, which contains 30 to 50% Ni by weight and Fe making up the remaining proportion, or a super invar alloy, which includes Co. The holes 48a of the base material 48 are made by punching after processing the raw material into flat shape, or the holes 48a are formed during casting by the precision casting (lost-wax process).
In a semiconductor, a silicon chip (silicon element) needs to be connected to other electrode directly or via a pad located on the silicon chip with wiring. In general, wiring material, such as aluminum wire, is used for wiring. However, when the wiring material is used, the element might be damaged during wire bonding. Further, when the temperature is increased due to heat generation during operation of the semiconductor, joint portions might be deteriorated or disconnected by the thermal stress caused by the difference between the thermal expansion of the wire and the silicon element.
To solve the above mentioned problem, Japanese Patent Publication No. 3216305 discloses a semiconductor having bonding pads. The bonding pads are located on a semiconductor layer, which serves as an active region of a semiconductor element. The bonding pads are electrically connected to electrodes outside the silicon element. The bonding pads of the semiconductor are connected to each other with plate-shaped conductive members.
When the cooling substrate 47 shown in FIG. 17(b) is rolled, spaces Δ are easily formed at portions where the thin metal wires 45a of the wire fabric 45 overlap with each other and in the vicinity of the overlapped portions as shown in FIG. 19, which is an enlarged partial cross sectional view of FIG. 17(b). As a result, air in the space Δ deteriorates the heat conductivity. Also, cracks are easily formed in the wire fabric 45 at the spaces Δ by the repeated thermal expansion and thermal contraction, which reduces the strength. To improve the strength of the wire fabric 45, the contact points of the thin metal wires 45a may be welded. However, it is difficult to weld the contact points of the wire fabric 45, since the wire fabric 45 is woven with the thin metal wires 45a and has fine mesh.
FIG. 20(b) illustrates a cooling substrate 51 according to another prior art. The cooling substrate 51 includes a flat metal plate 49. The metal plate 49 includes partitions 49b, which are arranged at predetermined intervals. Holes 49a are defined between the adjacent partitions 49b. The metal plate 49 is covered with a metal 50, which has higher coefficient of thermal expansion than the metal plate 49.
It is required to maximize the volumetric proportion of metal having low coefficient of thermal expansion to suppress the coefficient of thermal expansion of the cooling substrate. To suppress the coefficient of thermal expansion of the cooling substrate 47 shown in FIGS. 17(a), 17(b), 19, and 20(a), the wire fabric 45, which is woven with the thin metal wires 45a having low coefficient of thermal expansion, is used. However, when rolling, the metal plates 46, which have higher coefficient of thermal expansion than the thin metal wires 45a, cover the wire fabric 45 and enter portions 47a (see FIG. 20(a)) that correspond to bent portions of the thin metal wires 45a in addition to the meshes of the wire fabric 45. On the other hand, in the case with the cooling substrate 51 shown in FIG. 20(b), the metal 50 enters the holes 49a that correspond to the mesh of the wire fabric 45 shown in FIG. 20(a) and around the longitudinal ends of the metal plates 49. The longitudinal ends of each metal plate 49 are flat. Therefore, the metal that corresponds to the metal plates 46 that exist at the portions 47a shown in FIG. 20(a) does not exist in the cooling substrate 51 shown in FIG. 20(b). That is, the proportion of metal having high coefficient of thermal expansion in the cooling substrate 47 shown in FIG. 20(a) is greater than in the case with the cooling substrate 51 shown in FIG. 20(b) by the amount corresponding to the bent portions.
In the case where holes are formed by punching after processing a raw material into flat shape as the substrate for semiconductors shown in FIG. 18, the yield rate decreases, which increases the material cost. Also, forming the holes by precision casting (lost wax) increases the manufacturing cost.
In the process disclosed in Japanese Patent Publication No. 3216305, the difference between the coefficient of thermal expansion of the semiconductor element and the coefficient of thermal expansion of the plate-shaped conductive material is great. Thus, the thermal stress caused by heat generation during operation of the semiconductor might disconnect the wiring of the plate-shaped conductive material.

Composite structural material, and method of producing the same


This invention consists of a data communications interface that provides the means for an electronic, binary, data processing apparatus, or digital computer, to encode information in a base four format, and to communicate, with other data processing apparatuses, which utilize this invention, by exchanging base four digits, in a serial manner, via a standard data communications medium, such as a telephone line. This invention is composed of a serial communication device (SCD) and a line driver (LD). The SCD converts parallel, binary data to serial, base four data, and visa versa. The LD converts base four voltage levels to signals that are appropriate for the communications medium, and visa versa. A tone, for example, would be an appropriate signal for a telephone line. This invention enables information to be exchanged much more rapidly than is possible with a state of the art system.

1. Field of Invention
This invention relates to data transmitting and receiving interface devices, and more particularly to those devices that utilize asynchronous serial electronic communication.
2. Description of Prior art
Communication among digital systems, personal computers, has become a necessity in recent years with the advent of local area computer networks and the world wide web. Much of this communication is done via telephone line, cable, optical, or radio media, so the information must be exchanged in a serial manner. That is, only one piece of information is exchanged at a time. Serial communication among digital systems requires the use of special interface equipment. A typical state of the art serial communication network is shown in FIG. 1. The special interface equipment includes Universal Asynchronous Receiver Transmitters (UARTS), and line drivers. A detailed description of the operation of this state of the art network is given below.
The digital systems communicate with their respective UARTs in a parallel manner using the parallel interfaces 30 31. In parallel communication, binary words are exchanged. A binary word consists of several, typically sixteen, binary digits (bits). In the parallel interface, bits are represented by voltage levels. A logic zero is typically represented by zero volts, and a logic one is typically represented by five volts. A separate wire is required for each bit. A typical parallel interface will, therefore, contain sixteen communication wires plus two or three control wires.
The UARTs communicate with their respective line drivers in a serial manner using the serial interfaces 32 33. In serial communication, bits are exchanged sequentially. That is, the sending UART breaks up a binary word into bits and sends one bit at a time. The receiving UART receives one bit at a time and combines the bits into binary words. The number of bits transmitted in a second is known as the baud rate. In a typical serial interface, the bits are represented by either voltage or current levels, and a typical serial interface will contain one or two communication wires and two or three control wires.
The line drivers communicate with each other via the communication medium 34. The sending line driver, first, converts each bit, received from its UART, into an appropriate voltage level, current, tone, light pulse, or radio frequency, and, then, sends the signal out over the communication medium. The receiving line driver, first, converts the received signal to a voltage level, and, then, sends this voltage level to the respective UART.
To summarize, a binary word is transferred from one digital system to another as follows. The sending digital system sends a binary word to the respective UART. The UART breaks up the binary word into bits and sends each bit, sequentially, to the respective line driver. The line driver converts each bit into an appropriate signal, and sends the signal out over the communication medium. The receiving line driver converts the received signal into a bit and sends this bit to the respective UART. The UART combines the bits into a binary word, and sends the word to the respective digital system. The receiving digital system receives the binary word.
This communication process is slow, since only one bit can be transferred at a time. A state of the art system operates at 56K baud, and this means that the transfer of a one megabit file would require at least eighteen seconds.
Several solutions have been proposed to increase the throughput of bits, but thus far, no solution has been proposed that would enable the serial transfer of more than one bit at a time.


A system and method is provided to automatically generate content for ITV products and services by processing primary media sources. In one embodiment of the invention, keywords are automatically extracted from the primary media sources using one or more of a variety of techniques directed to video, audio and/or textual content of the multimodal source. In some embodiments, keywords are then processed according to one or more disclosed algorithms to narrow the quantity of downstream processing that is necessary to associate secondary sources (reference items) with the primary video source. Embodiments of the invention also provide automatic searching methods for the identification of reference items based on the processed keywords in order to maximize the value added by the association of reference items to the video source.

1. Field of the Invention
The invention relates generally to the field of interactive television. More specifically, the invention relates to a system and method for authoring interactive television content.
2. Description of the Related Art
Techniques for delivering interactive television (ITV) content to end users are well known in the art. For example, Metadata such as title, actor, and/or duration can be associated with movies, and users of Video on Demand (VOD) systems can select a movie for viewing at a television local to the user.
Various schemes have also been disclosed in the related art for allowing a user to select secondary content when viewing primary media content. For example, a movie chase scene may present to a user an icon for a particular brand of automobile depicted in the movie chase scene. If a user makes a selection during the display of the icon, the user is presented with secondary content in the form of advertisement for the selected brand of automobile, for instance, and the primary media content is paused. The secondary content may be in the form of a Web Page, where, for example, a Uniform Resource Locator (URL) has been associated with the icon.
Related art systems and methods for delivering ITV content have many disadvantages, however. For example, many delivery schemes begin with the assumption that secondary content has already been associated with the primary media content. In reality, there is a dearth of secondary content associated with most primary media content. In addition, the identification of secondary content, and association of the secondary content with the primary media content, are typically manual processes performed at, for example, a manual editing station. Such manual processes are time consuming and expensive. One consequence is that both primary and secondary content may not be relevant to current events. Moreover, for many content providers, manual editing is cost-prohibitive unless there is a reasonable expectation for mass market consumer appeal.
An inherent disadvantage of manual editing is that a human editor must make decisions about what portions of the primary media source might be appropriate for association with secondary content. The editor must also make decisions about the secondary content itself. Thus, the entertainment value and utility of resulting ITV products and services are highly dependent upon the skill and bias of the human editor that is authoring the ITV content.
Therefore, a need exists for a system and method for authoring ITV content without the long cycle time, high cost, and significant degree of variability associated with manual ITV content generation systems and methods.

System and method for automatically authoring interactive television content


The disclosure provides conjugates of anti-ASGR1 antibodies or antigen binding fragments thereof to a myeloid cell agonist, compositions comprising the conjugates, and methods of treating liver viral infections with the conjugates. The disclosure also provides for anti-ASGR1 antibodies or antigen binding fragments thereof and methods for using the antibodies or antigen binding fragments thereof in treating liver viral infections.

Millions of people worldwide are affected by viral infections of the liver, such as Hepatitis B (HBV) or Hepatitis C (HCV). These infections can be chronic, leading to cirrhosis and significant liver damage. In 2015, 1.3 million individuals died from HBV and HCV infections. Although antiviral medications can be used to treat these infections, treatment is not always effective. This is due, in part, because viruses such as HBV can achieve immunological ignorance or tolerance and avoid detection by the innate immune system. Therefore, there is a need for alternative strategies to treat viral infections of the liver.

Anti-ASGR1 antibody TLR8 agonist comprising conjugates and uses thereof


An abrasive composition comprising composite non-polymeric organic particles that is useful for chemical mechanical planarization (CMP), and which can widely be used in the semiconductor industry. The composite particles individually contain at least one nonpolymeric organic component and at least one other chemical component different from the at least one nonpolymeric organic component. The slurry composition can be vastly simplified if one or more of the components are incorporated into the abrasive particles. The abrasive compositions provide an efficient polishing rate, excellent selectivity and good surface quality when utilized as a new abrasive composition in CMP applications.

CMP is a technology used in the fabrication of advanced memory and logic devices for a wide range of applications. The pure substrate surface and complex surface of semiconductor wafer, dielectric layer, conducting wire and barrier materials in the integrated circuits have to be polished to achieve a certain degree of planarity, which is extremely important to reach a high density of integrated circuits. In general, CMP technology consists of three specific key components including polisher, consumables (pad and slurry), and post-CMP clean. The CMP slurry provides a chemical environment to wet and adjust the interaction between abrasive, pad and the wafer surface, and also moderates the mechanical force on the polishing surface. The slurry plays a key role in CMP process and determines the production efficiency and product quality.
The present invention relates generally to the preparation of semiconductor devices and more particularly to improved slurry compositions for the CMP of metal (e.g., Cu) layers and barrier materials (e.g., Ta, TaN, etc.).
Surface planarity is of paramount importance in microelectronics. With the integrated technology approaching the era of Ultra Large Scale Integration (ULSI), CMP is touted as the only viable technique to meet today's planarity requirements. Some of the most important issues in CMP today include dishing and erosion, corrosion, defects of the surface, the control of polishing rate and selectivity among different materials on the surface. The prior art attempts to accomplish these goals as follows.
U.S. Pat. No. 4,959,113 discloses a method of polishing metal surfaces with aqueous slurries. The slurry composition comprises water, abrasive such as SiO2, Al2O3, TiO2, ZrO2, CeO2, SnO2, SiC, TiC, and a salt containing any cation of group IIA, IIIA, IVA, or IVB and any anion of chloride, bromide, iodide, nitrate, sulfate phosphate, or perchlorate. The patent also discloses a pH range of 1-6 adjusted with mineral acids.
U.S. Pat. No. 5,084,071 discloses the CMP slurry, which comprises abrasive particles, e.g. SiO2, CeO2, Fe2O3, SiC, Si3N4, containing less than 1% (w/w) of alumina, a transition metal chelated salt (e.g. EDTA) as a polishing accelerator.
U.S. Pat. No. 5,114,437 discloses the CMP slurry for polishing aluminum substrate, which contains an alumina with an average particle size of 0.2-0.5 μm, and a polishing accelerator from the group consisting of chromium (III) nitrate, lanthanum nitrate, ammonium cerium (III) nitrate and neodymium nitrate.
U.S. Pat. No. 5,209,816 discloses a method for polishing Al— or Ti-containing metal layer with the CMP slurry, which contains inorganic abrasive materials, 0.1-20% by volume of H3PO4 and 1-30% by volume of H2O2.
U.S. Pat. No. 5,225,034 discloses the CMP slurry for polishing copper layer on a semiconductor wafer to produce copper wire on the wafer. The slurry comprises AgNO3, inorganic abrasive particles and an oxidant selected from H2O2, HClO, KClO, K2MnO4, or CH3COOOH.
U.S. Pat. No. 5,340,370 discloses the CMP slurry for polishing tungsten or tungsten nitride film, which comprises an oxidizing agent such as potassium ferricyanide, inorganic abrasive particles, water, and has a pH in 2-4.
U.S. Pat. No. 5,366,542 discloses a CMP slurry comprising alumina abrasive particles, chelating agent selected from the group consisting of polyaminocarboxylic acid (EDTA) and sodium or potassium salts, and further may contain boehmite or aluminum salt.
U.S. Pat. No. 5,391,258 discloses CMP slurry for polishing silicon, silica or silicate composite. The slurry comprises, in addition to inorganic abrasive particles, hydrogen peroxide and potassium hydrogen phthalate.
U.S. Pat. No. 5,516,346 discloses CMP slurry for titanium film. The slurry contains potassium fluoride, inorganic abrasive particles such as silica, and pH<8.
U.S. Pat. No. 5,527,423 discloses the slurry for polishing a metal layer, which comprises an oxidizing agent such as iron nitrate, alumina particles containing at least 50% gamma phase, nonionic surfactants such as polyalkyl siloxanes, or polyoxyalkylene ethers.
U.S. Pat. No. 6,171,352 discloses a CMP slurry which contains, in addition to inorganic abrasive particles, an abrasion accelerator, wherein the abrasion accelerator comprises monocarboxy group- or an amino group-containing compound and optionally a nitrate salt, also a viscosity modifier such as polyacrylic acid or its copolymer.
U.S. Pat. No. 6,258,721 discloses a CMP slurry of using diamond particles as an abrasive material, comprising ingredients such as an oxidizing agent, chelating agent, surfactant and others.
All of the above reported CMP slurries employ inorganic particles as abrasive materials and fail to adequately control dishing and erosion, corrosion, defects of the surface, polishing rate and selectivity among different materials on the surface.
Another approach to preparing CMP slurries is to use organic polymeric particles as the abrasive material. Such organic polymeric particle containing abrasive materials are disclosed in U.S. Pat. No. 6,620,215. Also, U.S. Pat. No. 6,576,554 teaches a slurry for CMP having a liquid and a plurality of polishing particles, wherein the polishing particle contains a composite particle formed by thermocompressing polymeric organic particles and inorganic particles. However, none of these patents teach or suggest the use of organic non-polymeric abrasive particles in the CMP slurries nor their unexpectedly superior properties.
In U.S. patent application Ser. No. 10/734,232, now U.S. Pat. No. 7,037,351, a set of non-polymeric organic particles are employed as abrasive materials in the formulation of metal CMP slurries. The invention emphasized the importance of surface properties of the particles and the art of formulating metal CMP slurries using such non-polymeric organic particles. This is distinct from the present invention which adds to the art by teaching abrasive particles, which are engineered so they carry specifically designed functions.

Engineered non-polymeric organic particles for chemical mechanical planarization


An optical apparatus comprising at least two optoelectronic devices fabricated on the same substrate and in thermal communication with each other. A first optoelectronic device is configured to generate optical signals and provide them to an optical system via an optical output port. A second optoelectronic device is configured to provide heat compensation for the first optoelectronic device. An electrical circuitry provides first electrical signals to the first optoelectronic device and second electrical signals to the second optoelectronic device. The electrical circuitry is configured to adjust at least the second electrical signals to controllably adjust a temperature of the first optoelectronic device.

The aspect ratios and fabrication methods of optoelectronic devices (e.g., tunable lasers and tunable laser transmitters) can result in excess real estate relative to the size of the optoelectronic device. For example, most single-mode tunable lasers and tunable laser transmitters have a waveguide ridge that is approximately 1 micron to 7 microns wide, whereas a typical transmitter chip on which the optoelectronic device is fabricated is configured for cleaving and handling and has a width in a range of 100 microns to 500 microns (e.g., in a range of 250 microns to 500 microns). A defect in any part of the optoelectronic device can cause the entire chip to be discarded, resulting in decreased yield and increased manufacturing costs.
Furthermore, a smaller foot print for the optoelectronic device may not be compatible with good thermal management. Accordingly, while larger chips with greater surface area can advantageously help with heat dissipation, such chips can have a larger amount of wasted space.

Multiple optoelectronic devices with thermal compensation