Patents Represented by Attorney, Agent or Law Firm John P. Hohimer
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Patent number: 5790730Abstract: A structure and method for packaging an integrated optic circuit. The package comprises a first wall having a plurality of microlenses formed therein to establish channels of optical communication with an integrated optic circuit within the package. A first registration pattern is provided on an inside surface of one of the walls of the package for alignment and attachment of the integrated optic circuit. The package in one embodiment may further comprise a fiber holder for aligning and attaching a plurality of optical fibers to the package and extending the channels of optical communication to the fibers outside the package. In another embodiment, a fiber holder may be used to hold the fibers and align the fibers to the package. The fiber holder may be detachably connected to the package.Type: GrantFiled: November 10, 1994Date of Patent: August 4, 1998Inventors: Stanley H. Kravitz, G. Ronald Hadley, Mial E. Warren, Richard F. Carson, Marcelino G. Armendariz
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Patent number: 5789745Abstract: An apparatus and method is provided for separating and analyzing chemical species in an ion mobility spectrometer using a frequency-domain technique wherein the ions generated from the chemical species are selectively transported through an ion flow channel having a moving electrical potential therein. The moving electrical potential allows the ions to be selected according to ion mobility, with certain of the ions being transported to an ion detector and other of the ions being effectively discriminated against. The apparatus and method have applications for sensitive chemical detection and analysis for monitoring of exhaust gases, hazardous waste sites, industrial processes, aerospace systems, non-proliferation, and treaty verification. The apparatus can be formed as a microelectromechanical device (i.e. a micromachine).Type: GrantFiled: October 28, 1997Date of Patent: August 4, 1998Assignee: Sandia CorporationInventors: Stephen J. Martin, Michael A. Butler, Gregory C. Frye, W. Kent Schubert
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Patent number: 5786231Abstract: A method for screening or qualifying semiconductor substrates for integrated circuit fabrication. The method comprises the steps of annealing at least one semiconductor substrate at a first temperature in a defect-activating ambient (e.g. hydrogen, forming gas, or ammonia) for sufficient time for activating any defects within on oxide layer of the substrate; measuring a defect-revealing electrical characteristic of at least a portion of the oxide layer for determining a quantity of activated defects therein; and selecting substrates for which the quantity of activated defects is below a predetermined level. The defect-revealing electrical characteristic may be a capacitance-versus-voltage (C-V) characteristic or a current-versus-voltage (I-V) characteristic that is dependent on an electrical charge in the oxide layer generated by the activated defects. Embodiments of the present invention may be applied for screening any type of semiconductor substrate or wafer having an oxide layer formed thereon or therein.Type: GrantFiled: December 5, 1995Date of Patent: July 28, 1998Assignee: Sandia CorporationInventors: William L. Warren, Karel J. R. Vanheusden, James R. Schwank, Daniel M. Fleetwood, Marty R. Shaneyfelt, Peter S. Winokur, Roderick A. B. Devine
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Patent number: 5783340Abstract: A method is disclosed for photolithographically defining device features up to the resolution limit of an auto-focusing projection stepper when the device features are to be formed in a wafer cavity at a depth exceeding the depth of focus of the stepper. The method uses a focusing cavity located in a die field at the position of a focusing light beam from the auto-focusing projection stepper, with the focusing cavity being of the same depth as one or more adjacent cavities wherein a semiconductor device is to be formed. The focusing cavity provides a bottom surface for referencing the focusing light beam and focusing the stepper at a predetermined depth below the surface of the wafer, whereat the device features are to be defined.Type: GrantFiled: July 31, 1997Date of Patent: July 21, 1998Assignee: Sandia CorporationInventors: Anthony J. Farino, Stephen Montague, Jeffry J. Sniegowski, James H. Smith, Paul J. McWhorter
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Patent number: 5780867Abstract: A broadband light-emitting diode. The broadband light-emitting diode (LED) comprises a plurality of III-V compound semiconductor layers grown on a semiconductor substrate, with the semiconductor layers including a pair of cladding layers sandwiched about a strained-quantum-well active region having a plurality of different energy bandgaps for generating light in a wavelength range of about 1.3-2 .mu.m. In one embodiment of the present invention, the active region may comprise a first-grown quantum-well layer and a last-grown quantum-well layer that are oppositely strained; whereas in another embodiment of the invention, the active region is formed from a short-period superlattice structure (i.e. a pseudo alloy) comprising alternating thin layers of InGaAs and InGaAlAs.Type: GrantFiled: March 7, 1996Date of Patent: July 14, 1998Assignee: Sandia CorporationInventors: Ian J. Fritz, John F. Klem, Michael J. Hafich
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Patent number: 5781017Abstract: An electron beam apparatus and method for testing a circuit. The electron beam apparatus comprises an electron beam incident on an outer surface of an insulating layer overlying one or more electrical conductors of the circuit for generating a time varying or alternating current electrical potential on the surface; and a measurement unit connected to the circuit for measuring an electrical signal capacitively coupled to the electrical conductors to identify and map a conduction state of each of the electrical conductors, with or without an electrical bias signal being applied to the circuit. The electron beam apparatus can further include a secondary electron detector for forming a secondary electron image for registration with a map of the conduction state of the electrical conductors.Type: GrantFiled: April 26, 1996Date of Patent: July 14, 1998Assignee: Sandia CorporationInventors: Edward I. Cole, Jr., Kenneth A. Peterson, Daniel L. Barton
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Patent number: 5757536Abstract: An electrically-programmable diffraction grating. The programmable grating includes a substrate having a plurality of electrodes formed thereon and a moveable grating element above each of the electrodes. The grating elements are electrostatically programmable to form a diffraction grating for diffracting an incident beam of light as it is reflected from the upper surfaces of the grating elements. The programmable diffraction grating, formed by a micromachining process, has applications for optical information processing (e.g. optical correlators and computers), for multiplexing and demultiplexing a plurality of light beams of different wavelengths (e.g. for optical fiber communications), and for forming spectrometers (e.g. correlation and scanning spectrometers).Type: GrantFiled: August 30, 1995Date of Patent: May 26, 1998Assignee: Sandia CorporationInventors: Antonio J. Ricco, Michael A. Butler, Michael B. Sinclair, Stephen D. Senturia
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Patent number: 5726805Abstract: An optical filter includes a dielectric layer formed within a resonant optical cavity, with the dielectric layer having formed therein a sub-wavelength periodic structure to define, at least in part, a wavelength for transmission of light through the resonant optical cavity. The sub-wavelength periodic structure can be formed either by removing material from the dielectric layer (e.g. by etching through an electron-beam defined mask), or by altering the composition of the layer (e.g. by ion implantation). Different portions of the dielectric layer can be patterned to form one or more optical interference filter elements having different light transmission wavelengths so that the optical filter can filter incident light according to wavelength and/or polarization. For some embodiments, the optical filter can include a detector element in optical alignment with each optical interference filter element to quantify or measure the filtered light for analysis thereof.Type: GrantFiled: June 25, 1996Date of Patent: March 10, 1998Assignee: Sandia CorporationInventors: Sumanth Kaushik, Brian R. Stallard
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Patent number: 5726462Abstract: A semiconductor structure. The semiconductor structure comprises a plurality of semiconductor layers formed on a substrate including at least one layer of a III-V compound semiconductor alloy comprising aluminum (Al) and antimony (Sb), with at least a part of the AlSb-alloy layer being chemically converted by an oxidation process to form superposed electrically insulating and electrically conducting portions. The electrically insulating portion formed from the AlSb-alloy layer comprises an oxide of aluminum (e.g. Al.sub.2 O.sub.3), while the electrically conducting portion comprises Sb.Type: GrantFiled: February 7, 1996Date of Patent: March 10, 1998Assignee: Sandia CorporationInventors: Olga B. Spahn, Kevin L. Lear
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Patent number: 5712865Abstract: A temperature-insensitive vertical-cavity surface-emitting laser (VCSEL) and method for fabrication thereof. The temperature-insensitive VCSEL comprises a quantum-well active region within a resonant cavity, the active region having a gain spectrum with a high-order subband (n.gtoreq.2) contribution thereto for broadening and flattening the gain spectrum, thereby substantially reducing any variation in operating characteristics of the VCSEL over a temperature range of interest. The method for forming the temperature-insensitive VCSEL comprises the steps of providing a substrate and forming a plurality of layers thereon for providing first and second distributed Bragg reflector (DBR) mirror stacks with an active region sandwiched therebetween, the active region including at least one quantum-well layer providing a gain spectrum having a high-order subband (n.gtoreq.Type: GrantFiled: September 28, 1995Date of Patent: January 27, 1998Assignee: Sandia CorporationInventors: Weng W. Chow, Kent D. Choquette, Paul L. Gourley
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Patent number: 5706840Abstract: A precision cleaning apparatus and method. The precision cleaning apparatus includes a cleaning monitor further comprising an acoustic wave cleaning sensor such as a quartz crystal microbalance (QCM), a flexural plate wave (FPW) sensor, a shear horizontal acoustic plate mode (SH--APM) sensor, or a shear horizontal surface acoustic wave (SH--SAW) sensor; and measurement means connectable to the sensor for measuring in-situ one or more electrical response characteristics that vary in response to removal of one or more contaminants from the sensor and a workpiece located adjacent to the sensor during cleaning. Methods are disclosed for precision cleaning of one or more contaminants from a surface of the workpiece by means of the cleaning monitor that determines a state of cleanliness and any residual contamination that may be present after cleaning; and also for determining an effectiveness of a cleaning medium for removing one or more contaminants from a workpiece.Type: GrantFiled: March 3, 1995Date of Patent: January 13, 1998Assignee: Sandia CorporationInventors: Thomas W. Schneider, Gregory C. Frye, Stephen J. Martin
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Patent number: 5693580Abstract: Alkaline-earth lanthanoborate sealing-glass compositions containing CaO, La.sub.2 O.sub.3, B.sub.2 O.sub.3, TiO.sub.2 and Al.sub.2 O.sub.3 in various combinations of mole-% are provided. These sealing-glass compositions are useful for forming hermetic glass-to-metal seals with titanium and titanium alloys that have a high aqueous durability for component or device applications requiring exposure to moisture, water or body fluids. Particular applications of the titanium sealing-glass compositions include forming glass-to-metal seals for lithium batteries and implanted biomedical devices (e.g. batteries, pacemakers, defibrillators, pumps).Type: GrantFiled: September 13, 1996Date of Patent: December 2, 1997Assignee: Sandia CorporationInventors: Richard K. Brow, Howard L. McCollister, Carol C. Phifer, Delbert E. Day
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Patent number: 5684308Abstract: A digital photoreceiver is formed monolithically on an InP semiconductor substrate and comprises a p-i-n photodetector formed from a plurality of InP/InGaAs layers deposited by an epitaxial growth process and an adjacent heterojunction bipolar transistor (HBT) amplifier formed from the same InP/InGaAs layers. The photoreceiver amplifier operates in a large-signal mode to convert a detected photocurrent signal into an amplified output capable of directly driving integrated circuits such as CMOS. In combination with an optical transmitter, the photoreceiver may be used to establish a short-range channel of digital optical communications between integrated circuits with applications to multi-chip modules (MCMs). The photoreceiver may also be used with fiber optic coupling for establishing longer-range digital communications (i.e. optical interconnects) between distributed computers or the like.Type: GrantFiled: February 15, 1996Date of Patent: November 4, 1997Assignee: Sandia CorporationInventors: Michael L. Lovejoy, Benny H. Rose, David C. Craft, Paul M. Enquist, David B. Slater, Jr.
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Patent number: 5661233Abstract: An acoustic-wave sensor apparatus and method. The apparatus for analyzing a normally liquid petroleum-based composition includes at least one acoustic-wave device in contact with the petroleum-based composition for sensing or detecting the presence of constituents (e.g. paraffins or petroleum waxes) therein which solidify upon cooling of the petroleum-based composition below a cloud-point temperature. The acoustic-wave device can be a thickness-shear-mode device (also termed a quartz crystal mircrobalance), a surface-acoustic-wave device, an acoustic-plate-mode device or a flexural plate-wave device. Embodiments of the present invention can be used for measuring a cloud point, a pour point and/or a freeze point of the petroleum-based composition, and for determining a temperature characteristic of each point.Type: GrantFiled: March 26, 1996Date of Patent: August 26, 1997Assignee: Sandia CorporationInventors: James J. Spates, Stephen J. Martin, Arthur J. Mansure
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Patent number: 5648302Abstract: Barium lanthanoborate sealing-glass compositions are provided comprising various combinations (in terms of mole-%) of boron oxide (B.sub.2 O.sub.3), barium oxide (BaO), lanthanum oxide (La.sub.2 O.sub.3), and at least one other oxide selected from the group consisting of aluminum oxide (Al.sub.2 O.sub.3), calcium oxide (CaO), lithium oxide (Li.sub.2 O), sodium oxide (Na.sub.2 O), silicon dioxide (SiO.sub.2), or titanium dioxide (TiO.sub.2). These sealing-glass compositions are useful for forming hermetic glass-to-metal seals with titanium and titanium alloys having an improved aqueous durability and favorable sealing characteristics. Examples of the sealing-glass compositions are provided having coefficients of thermal expansion about that of titanium or titanium alloys, and with sealing temperatures less than about 900.degree. C., and generally about 700.degree.-800.degree. C.Type: GrantFiled: September 13, 1996Date of Patent: July 15, 1997Assignee: Sandia CorporationInventors: Richard K. Brow, Howard L. McCollister, Carol C. Phifer, Delbert E. Day
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Patent number: 5633527Abstract: A unitary lens semiconductor device and method. The unitary lens semiconductor device is provided with at least one semiconductor layer having a composition varying in the growth direction for unitarily forming one or more lenses in the semiconductor layer. Unitary lens semiconductor devices may be formed as light-processing devices such as microlenses, and as light-active devices such as light-emitting diodes, photodetectors, resonant-cavity light-emitting diodes, vertical-cavity surface-emitting lasers, and resonant cavity photodetectors.Type: GrantFiled: February 6, 1995Date of Patent: May 27, 1997Assignee: Sandia CorporationInventor: Kevin L. Lear
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Patent number: 5625635Abstract: An infrared emitting device and method. The infrared emitting device comprises a III-V compound semiconductor substrate upon which are grown a quantum-well active region having a plurality of quantum-well layers formed of a ternary alloy comprising InAsSb sandwiched between barrier layers formed of a ternary alloy having a smaller lattice constant and a larger energy bandgap than the quantum-well layers. The quantum-well layers are preferably compressively strained to increase the threshold energy for Auger recombination; and a method is provided for determining the preferred thickness for the quantum-well layers. Embodiments of the present invention are described having at least one cladding layer to increase the optical and carrier confinement in the active region, and to provide for waveguiding of the light generated within the active region.Type: GrantFiled: November 28, 1994Date of Patent: April 29, 1997Assignee: Sandia CorporationInventors: Steven R. Kurtz, Robert M. Biefeld, L. Ralph Dawson, Arnold J. Howard, Kevin C. Baucom
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Patent number: 5624529Abstract: A dry etching method. According to the present invention, a gaseous plasma comprising, at least in part, boron trichloride, methane, and hydrogen may be used for dry etching of a compound semiconductor material containing layers including aluminum, or indium, or both. Material layers of a compound semiconductor alloy such as AlGaInP or the like may be anisotropically etched for forming electronic devices including field-effect transistors and heterojunction bipolar transistors and for forming photonic devices including vertical-cavity surface-emitting lasers, edge-emitting lasers, and reflectance modulators.Type: GrantFiled: May 10, 1995Date of Patent: April 29, 1997Assignee: Sandia CorporationInventors: Randy J. Shul, Christopher Constantine
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Patent number: 5608519Abstract: An apparatus and method for microscopic and spectroscopic analysis and processing of biological cells. The apparatus comprises a laser having an analysis region within the laser cavity for containing one or more biological cells to be analyzed. The presence of a cell within the analysis region in superposition with an activated portion of a gain medium of the laser acts to encode information about the cell upon the laser beam, the cell information being recoverable by an analysis means that preferably includes an array photodetector such as a CCD camera and a spectrometer. The apparatus and method may be used to analyze biomedical cells including blood cells and the like, and may include processing means for manipulating, sorting, or eradicating cells after analysis thereof.Type: GrantFiled: March 20, 1995Date of Patent: March 4, 1997Inventors: Paul L. Gourley, Mark F. Gourley
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Patent number: 5571944Abstract: Moisture corrosive gas stream is measured as a function of the difference in resonant frequencies between two acoustic wave (AW) devices, each with a film which accepts at least one of the components of the gas stream. One AW is located in the gas stream while the other is located outside the gas stream but in the same thermal environment. In one embodiment, the film is a hydrophilic material such as SiO.sub.2. In another embodiment, the SiO.sub.2 is covered with another film which is impermeable to the corrosive gas, such that the AW device in the gas stream measures only the water vapor. In yet another embodiment, the film comprises polyethylene oxide which is hydrophobic and measures only the partial pressure of the corrosive gas. Other embodiments allow for compensation of drift in the system.Type: GrantFiled: December 20, 1994Date of Patent: November 5, 1996Assignee: Sandia CorporationInventors: Kent B. Pfeifer, Gregory C. Frye, Thomas W. Schneider