Abstract: A differentiable ablation approach to patterning dielectrics which are not of the same absorbance uses an absorbant dielectric at a specified laser wavelength over a non-absorbant dielectric at that wavelength. The absorbant dielectric may be laser-patterned and become an integral mask enabling plasma etching of the underlying non-absorbant dielectric. If the patterning of the absorbant dielectric involves vias, polymer ridges formed around via surfaces during laser patterning may be removed at the same time the underlying non-absorbant dielectric is etched using a transparent, oxygen plasma resistant mask. Alternatively, an inert mask may be used instead of the absorbant dielectric to allow plasma etching of the non-absorbant dielectric.

Abstract: A gate driver circuit for a converter which requires an approximately 50% duty cycle to drive two power switching devices (e.g., in many interleaved, push-pull and bridge converters) includes a single transformer secondary winding coupled between the gates of the two devices. The transformer is reset every half-cycle by driving each device in the forward, or positive, direction only. Advantageously, the result is an approximately 50% reduction in gate drive power as compared with conventional schemes requiring a negative gate drive voltage for turn-off.

Abstract: A high-throughput bidirectional data communication channel is formed of a pipelined plurality M of stages, connected to the input/output (I/O) port of each of the pair of devices using the channel, and configured to allow interruptibility of data transmission by either device connected to the channel; either device may be sender or receiver and transmission of data may be interrupted by either device for any number of cycles and resumed without loss or duplication of data at the receiver. The channel uses pipelining to achieve longer distance parallel transmission of N plural data bits, while maintaining the maximum high speed throughput. The channel, and its associated data transfer protocol, supports bidirectional transmission of data between the two sourcing/terminating devices with maximum throughput being achieved by transmitting a word of parallel data during every clock cycle.

Abstract: A plasticized polyetherimide, such as a blend of polyetherimide and a pentaerythritol tetrabenzoate ester, has been found useful as a low temperature laminating adhesive for making high density interconnect circuit arrays.

Abstract: A method for enabling a diagnostic system to assess, within time constraints, the health of the host system during operation, and to detect and isolate system faults during maintenance, with reduced potential for false alarms due to intermittent real faults and system noise, and for apparent misdiagnosis of the host system health, by use of a Diagnostics by Confidence Measure Assessment (DCMA) process in which a confidence measure is provided for each system test failure assessment, resulting from both the use of specialized persistence processing on many test results from a single source and the use of specialized corroboration processing on many test results from different sources.

Abstract: A moisture-proof integrated circuit module includes at least one integrated circuit component in a high density interconnect (HDI) structure fabricated by applying to a substrate successive multiple ply sequences having a plurality of via holes therein. The sequences overlie the component(s) and the module substrate, and each sequence includes a dielectric film and a plurality of lands comprised of metal that extends into the vias of the sequence to provide electrical interconnections. The module includes at least one moisture barrier film to prevent penetration of moisture through the module to the circuit component(s).

Abstract: A process and configuration are described which enable the I/O metal fingers of any high density interconnect (HDI) module to be extended over the edge of a substrate at the end of circuit fabrication, thus enabling fabrication of circuits for arrangement in three-dimensional stacks. The module includes a first dielectric layer covering one or more electrical conductors on a substrate. The first dielectric layer is ablated to expose a portion of at least one electrical conductor and a second dielectric layer is then applied over the first dielectric layer and the exposed portion of the electrical conductor except for an extremity of the conductor. A second electrical conductor is subsequently applied and patterned to cover a portion of the second dielectric layer, the extremity of the conductor, and at least a portion of one edge of the substrate.

Abstract: A method for fabricating a metal interconnection pattern for an integrated circuit module is provided comprising the steps of: aligning only one face of the module, forming a metal layer on at least one other face of the module, applying a coating of photoresist to the metal layer, exposing predetermined portions of the photoresist to reflected radiation, and shaping the metal layer in accordance with the exposed photoresist portions.

Abstract: A fault-tolerating memory system has a data memory with a large number (M+N) of data storage words each having a length greater than the length of user data to be stored in that word; the extra word length is used for at least an error-detecting-and-correcting (EDAC) code. The user data is stored in a smaller number (N) of the words, with the remaining number (M) of words being used to store a map of which portions, if any, of each word are not usable. The N words of user data storage can include S normal storage words and (N-S) spare words, each for use if one of the normal storage words has too many unusable portions. A portion of each word length can contain at least one spare word portion, to which a block of data can be moved if any bit of a like-sized portion of the normal storage word is unusable.

Abstract: A hermetic seal is provided for a conductive feedthrough through a thin ceramic component by a platinum or palladium lead by sealing the gap between the lead and the ceramic with a copper-copper oxide eutectic. The lead may have a copper coating on it prior to and subsequent to formation of the copper-copper oxide eutectic.

Abstract: This invention relates to an method and apparatus for soldering microelectronic lead connections to pads on a ceramic substrate with the aid of a fiber based Neodymium:yttrium-aluminum-garnet (Nd:YAG) laser. Such structures of this type, generally, provide a means of delivering sufficient localized heating to the ceramic substrate to reflow solder plate or melt solder cream (paste) within the lead connection without any substrate preheating.

Abstract: Chip adhesives with improved working time comprise a polyetherimide prepared from 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride and bis(4-aminophenyl) sulfone; at least one of silica and conductive metal particles, especially silver particles; and at least one substituted acetophenone as solvent. The preferred substituted acetophenone is 4-methylacetophenone.

Abstract: A method for determining the illumination of an illuminator at a selected point P in an image volume to be projected on an image screen surface by a computerized image generator, operates by: decomposing the illuminator into at least one of spherical, beam and cylindrical sources; determining a direction of incidence of the light from each source at point P in the image volume; determining the extent of the source and the attenuation of illumination with distance from that source; then determining a set of color light intensities at point P in the image volume due to the light from the particular source; and translating the incidence direction and color intensities from point P to a displayable incidence direction and a displayable set of color illumination intensities at a corresponding projection location on the image screen surface.

Abstract: A computerized router is provided with local protection regions in which the orientation of conductors in a given conductor layer is restricted to a particular orientation without affecting the allowable orientations of conductors in that layer in other portions of the routing area. Such local protection regions may apply to one or more signal conductor layers. This capability may be provided for a router which does not have it by the addition of artificial features to the components to be connected by the router. These features may be obstructions or conductors to be used in routing signal paths. Obstructions are sized and positioned to restrict conductors in the local protection regions to the desired orientation.

Abstract: A high acceleration object includes an electronic system which is operable at accelerations in excess of 20,000 g. Connections between integrated circuit chips and other portions of the electronic system are provided by metallization patterns disposed on polymer dielectric layers which are self-supporting across gaps between components. A high density interconnect structure is disposed within the cavity of a hermetically sealed package.

Abstract: Pin-mounted components, such as DIP-packaged devices, multi-pin toroids and memory cubes are integrated into high density interconnect (HDI) structures by external attachment. Frozen spheres of conductive epoxy are placed, using automated pick-and-place equipment, into laser-drilled well-like via holes in an HDI module and then thawed under temperature and vacuum, prior to component pin insertion. Precision dispensing and uniform dispersion of adhesive results.

Abstract: A method for optimally operating a computer numerical control (CNC) milling machine to form cavities in a ceramic substrate for receiving IC chips and other components of a high density interconnect structure electrically interconnected by a multi-layer interconnect (HDI) structure. Generation of the CNC program instructions is based on locations and dimensions of the components which, through a set of design rules, provide locations and dimensions for an initial set of cavities corresponding to the components on a one-for-one basis. Depending upon the particular arrangement of the components, specific neighboring cavities of the initial set may either overlap or be separated by walls. A representation of the location and dimensions of each of the cavities of the initial set is formed, and the representation is enhanced by a "combine pockets" step and by a "remove borders" step to represent locations and dimensions of cavities of an optimized set.

Abstract: In an optical system including a laser diode with astigmatism such that the apparent source position in two orthogonal axes each normal to the beam direction differ, a beam prism expander and a collimating lens positioned between the diode and expander, the collimated lens is positioned relative to the laser such that the radius of curvature of the light beam exiting the beam expander in the two axes is identical.

Abstract: A high-resolution radiation detector cell array has a planar substrate, with multiple switching circuits, interposed between a detector substrate and a subsequent substrate containing high-sensitivity preamplifiers; each of the middle-substrate switching circuits operates to substantially continuously connect cyclic different ones of an assigned different set of the array cells to an associated single one of multiple preamplifiers. In a N.times.M array of cells used with a C column-by-R row switching subassembly, a total array of (N/C).times.(M/R) preamplifiers are needed. The generally-planar detector, switch and preamplifier substrates can be connected using metallic "bump" contacts; the switch layer material may be selected to have a CTE between the CTEs of the detector and preamplifier layers.

Abstract: An optical disk includes a spiraling guide track embedded in a surface of the disk on either side of which is positioned a different information track. Apparatus for both tracking and reading the disk includes a source providing two light beams directed to the disk surface and spaced apart such as to nominally illuminate respective ones of the information tracks and part of the intermediate guide track. Detectors are positioned to receive reflected light from the disk to both provide signals corresponding to information on the disk and to track the beams relative to the disk so that they are located properly with respect to the location of the information tracks on the disk.