Abstract: A method for providing an underfill material on an integrated circuit chip at the wafer level. The wafer (10) typically contains one or more integrated circuit chips (12), and each integrated circuit chip typically has a plurality of solder bumps (34) on its active surface. The wafer is first diced (22) on the active surface side to form channels (38) that will ultimately define the edges (39) of each individual integrated circuit chip, the dicing being of such a depth that it only cuts part-way through the wafer. The front side (36) of the wafer is then coated (24) with an underfill material (40). Generally, a portion (45) of each solder bump remains uncoated, but in certain cases the bumps can be completely covered. The back side of the wafer is then lapped, ground, polished or otherwise treated (26) so as to remove material down to the level of the previously diced channels.

Abstract: A bumped semiconductor device (10) exhibiting enhanced pattern recognition when illuminated in a machine vision system. The semiconductor device has a substantially coplanar array of solder bumps (16) and a coating of underfill material (17) on one face. A fluxing composition (18) containing an image enhancing agent is selectively deposited over at least two of the solder bumps in the array to modify the optical characteristics of the solder bumps to cause the solder bumps to appear bright against the background of the underfill material when the semiconductor device is illuminated (19) by selected wavelengths of light.

Abstract: A wireless biopotential sensor includes an adhesive strip having a lower surface for placement against the skin of a patient and an upper surface. A pair of conductive electrodes are applied to the lower surface of the adhesive strip. A sensor substrate is applied to the upper surface. The sensor substrate includes first and second conductive contact pads that are placed in registry with the pair of conductive electrodes, with the contact pads arranged in electrical contact with the conductive electrodes. An electronics module is applied to the sensor substrate and arranged in electrical contact with the contact pads. The electronics module comprises a power supply and electronics for generating a wireless signal containing biopotential signals detected by the pair of conductive electrodes.

Abstract: A compact real-image projection apparatus is used for a portable device (140). An optical projector (110) emits light that is capable of forming an image. A collapsible screen (120) has a collapsed surface area no larger than substantially the surface area of a side of the portable device and an expanded surface area capable of receiving the light emitted from the optical projector (110). A retractable connecting member (150) is coupled between the screen (120) and the optical projector (110) and has at least a stowed position and an extended position. The extended position is configured to hold the screen (120) and the optical projector (110) relative to one another such that the light emitted from the optical projector forms a real image on the screen.

Abstract: A display (200) includes a slanted fringe volume hologram (206) or other optical element that steers light that passes into and out of the display (200) so as to provide angular separation between unmodulated scattered light and modulated reflected light. As a result of the angular separation the effective contrast of the display (200) is improved. By placing the slanted fringe volume hologram (206) below a front polarizer of the display a further reduction in the amount of unmodulated scatter light is achieved. The slanted fringe volume hologram is preferably a hologram of a diffusive object (328), and consequently exhibits a degree of light diffusion that results in a viewing zone of an appreciable angular extent.

Abstract: A color tunable pixel (100) includes a cholesteric liquid crystal (110). The helical pitch of the cholesteric liquid crystal (110) is controlled by applying electrical fields (202, 302) of varying strength and/or frequency perpendicular to an initial helical axis (H) of cholesteric liquid crystal (110) in order to shift the hue of light reflected by the cholesteric liquid crystal (110). The reflectivity of the cholesteric liquid crystal (110) may be controlled by applying an electric field (402) perpendicular to the initial helical axis (H) at a frequency at which the cholesteric liquid crystal (110) exhibits a negative dielectric anisotropy. Alternatively the visible light reflectivity may be controlled by applying an electric field to shift the reflectance of the cholesteric liquid crystal (110) into the infrared portion of the spectrum, or in another embodiment by allowing the cholesteric liquid crystal (110) to revert to an ultraviolet reflected state.

Abstract: A method for forming an embedded low profile capacitor in a multilayer printed circuit board. The method entails providing a first metal plate on a dielectric substrate. A dielectric layer of a photopolymeric material is applied onto a first region of the first metal plate, surrounded by a second region that is exposed. A second metal plate is deposited onto the dielectric layer and the second region of the first metal plate. The second plate is then patterned to decline an upper electrode on the dielectric layer that is electrically isolated from the first metal plate. This may be accomplished by forming a trench in the second metal plate above the dielectric layer. In one aspect, the resulting capacitor thus comprises a lower electrode structure derived mainly from the first metal plate, a dielectric layer overlying the first region of the first metal plate and an upper electrode overlying the dielectric layer.

Abstract: As part of a process to generate a private key for RSA™ digital signature generation on a smartcard, it is necessary to determine a modular inverse e−1 mod m of a data value e. In order to determine the modular inverse from a data value e and a value of m for the inversion, the value of m mod e is calculated by determining a remainder value r of m divided by e and then an inverse t=r−1 mod e is determined. The modular inverse e−1 mod m is then determined utilising at least the value t by determining a value w=e−t and then determining e−1 mod m by computing (q*w)+1+the integer part of ((w*r)/e).

Abstract: A two-way selective call device (106) for determining if a response was received to a message transmitted to a designation device including at least one switch (216) to construct the message having at least an identifiable character. An address book designates at least one destination device (106, 112, 116, 118) and a selector (216) selects a destination device (106) of the at least one destination device (106, 112, 116, 118) to receive the message. A transmitter (222) transmits the message to the destination device (106) and a timer (302) measures a first predetermined time. A processor (206) coupled to the receiver (204) monitors received messages during the first predetermined time period to determine when a response to the message was received and an output device (208, 212, 214) indicates when the response from the at least one identified destination device was not received within the first predetermined time period.

Abstract: An electronic tag assembly (100) includes a substrate (102) having an antenna pattern (104, 106) disposed thereon, an integrated circuit die (108) having electrical interface terminals (204, 206) that directly contact or interface with the antenna pattern (104, 106), and electrically non-conductive adhesive (202) interposed between the substrate and the integrated circuit die (108) that secures both together, and that maintains the integrity of the electrical interface. Preferably, a clamping force is exerted on the integrated circuit die (108) to maintain contact between the electrical terminals (204, 206) and the antenna pattern (104, 106) while the non-conductive adhesive (202) is being introduced.

Abstract: A microelectronic assembly includes a substrate having a plurality of bond pads disposed on a substantially planar die attach surface and an integrated circuit die having a die face and a plurality of bond pads of the die face. The die is provided with a polymeric bead about the outer edges of the die. Die face bond pads are aligned with corresponding substrate bond pads and electrically interconnected by heating to a reflow temperature. Exposure of the polymeric bead to the reflow temperature causes the bead to form a peripheral bond between the die and the substrate.

Abstract: A dielectric film is formed on a free-standing conductive metal layer to form a multi-layer foil comprising a conductive metal layer, a barrier layer and a dielectric oxide layer. Such multi-layer foils are mechanically flexible, and useful for the manufacture of capacitors. Examples of barrier layers include Ni—P or Ni—Cr alloys. After a second layer of conductive metal is deposited on a dielectric oxide surface opposing the first conductive metal layer, the resulting capacitor foil is processed into a capacitor. The resulting capacitor is a surface mounted capacitor or is formed as a integrated or embedded capacitor within a circuit board.

Abstract: Two document images which have been compressed using the JBIG-2 standard for facsimile applications so as to include a plurality of index numbers, one or more positions in each image associated with the index numbers, and a group symbol for each index number can be merged to form a final composite image. Firstly, two virtual indexed images are formed by patterns of the index numbers at their associated positions in the document images. The patterns of index numbers in the two virtual indexed images are then compared (22) to determine whether there is correlation between the patterns of index numbers in at least parts of the two virtual indexed images. The two virtual indexed images are then merged (25), when there is a sufficient correlation, such that the parts that correlate overlap each other to provide a merged virtual indexed image, and then the index numbers in the merged virtual indexed image are replaced (7) by the corresponding group symbol to provide the final composite image.

Abstract: A communications system (100) includes a multi-rate source coder (MRSC) (102), a variable size/rate buffer (VSRB) (112), a speech buffer (104), and a buffer control block (106). The variable size/rate buffer (112) includes a source coder bit buffer (SCBB) (114) and an adaptive transmit frame buffer (116). The source coder bit buffer (114) receives speech frames coded at different rates from the multi-rate source coder (102), and deposits an integer or non-integer number of frames in the adaptive transmit frame buffer (ATFB) (116). A receiver includes a seamless rate transition module (SRTM) (308) and an variable buffer (310). The seamless rate transition module (308) correlates speech data previously coded at different rates, and it then truncates or alternatively appends, concatenates, and warps the speech data to remove any annoying artifacts at the rate change boundary.

Abstract: A system for enhancing the signal-to-noise ratio of a speech signal is avoided. A plurality of local energy maximums associated with a speech signal are determined. Presumably, each of these local energy maximums defines a speech pitch period. Typically, human pitch periods are approximately 100-400 Hz depending on the sex and age of the speaker. Because human speech typically includes more energy near the beginning of a pitch period than at the end of the pitch period, and background noise tends to remain relatively constant throughout the pitch period, the speech signal may be enhanced by increasing the energy associated with the beginning of the pitch period and/or by decreasing the energy associated with the end of the pitch period. Preferably, the amount of energy increase in the earlier portion of the pitch period is approximately equal to the amount of energy reduction in the later portion of the pitch period. In this manner, the total energy remains the constant.

Abstract: A thin-film metal resistor (44) suitable for a multilayer printed circuit board (12), and a method for its fabrication. The resistor (44) generally has a multilayer construction, with the individual layers (34, 38) of the resistor (44) being self-aligned with each other so that a negative mutual inductance is produced that very nearly cancels out the self-inductance of each resistor layer (34, 38). As a result, the resistor (44) has a very low net parasitic inductance. In addition, the multilayer construction of the resistor (44) reduces the area of the circuit board (12) required to accommodate the resistor (44), and as a result reduces the problem of parasitic interactions with other circuit elements on other layers of the circuit board (12).

Abstract: An apparatus for selecting a cohort model for use in a speaker verification system includes a model generator (108) for determining a target speaker model (114) from a speech sample collected from the target speaker (106). A cohort selector (110) determines a similarity value between each of a number of predetermined existing speaker models from a model pool (112) and the target speaker model (114) and a dissimilarity value between each of the existing speaker models and any previously selected cohort models (116). An existing speaker model which is most similar to the target speaker model, but most dissimilar to previously chosen cohort models, is then chosen as another cohort model for the target speaker.

Abstract: Quantization unit (108) comprises evaluator (120) and comparator (122) in signal processing for identifying an utterance in system (100). The evaluator (120) weights a first intermediate result of an operation on a first set of a plurality of speech parameters (104) differently than a second intermediate result of an operation on a second set of the plurality of speech parameters (104) in a weighted representation of the plurality of speech parameters (104). The comparator (122) employs the weighted representation of the plurality of speech parameters (104) to determine a vector index to represent the plurality of speech parameters (104). The quantization unit (108), in one example, can employ split vector quantization in conjunction with the weighted representation to determine a vector index to represent the plurality of speech parameters (104).

Abstract: Antenna weights for a transmit path (3) between two communication devices (1, 2), the first device (1) having an antenna array (4, 5, 6) are generated in the second device (2) and fed back to weighting circuitry (9, 10, 11, 12) in the first device (1). The invention is particularly applicable to multicarrier systems such as OFDM systems. Only weights for those sub-carriers identified as being received with comparatively poor signal quality are calculated and fed back to the first device (1), thus limiting the additional overhead requirements to a minimum.