Patents Represented by Attorney, Agent or Law Firm Peter A. Businger
  • Patent number: 4853753
    Abstract: A semiconductor integrated resonant-tunneling device having multiple negative-resistance regions, and having essentially equal current peaks in such regions, is useful as a highly compact element, e.g., in apparatus designed for ternary logic operations, frequency multiplication, waveform scrambling, memory operation, parity-bit generation, and coaxial-line driving. The device can be made by layer deposition on a substrate and includes a resonant-tunneling structure between contacts such that side-by-side first and third contacts are on one side, and a second contact is on the opposite side of the resonant-tunneling structure. Disclosed further are (two-terminal) resonant-tunneling diodes as incorporated in memory devices, e.g., in lieu of 2-transistsor flip-flops; room-temperature device operation; and devices comprising an essentially undoped accelerator region between an emitter contact and a resonant-tunneling structure.
    Type: Grant
    Filed: November 5, 1987
    Date of Patent: August 1, 1989
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Federico Capasso, Alfred Y. Cho, Susanta Sen
  • Patent number: 4851895
    Abstract: Metallization of integrated devices using ruthenium as a metallization material results in well-adhering contacts to source and drain regions as well as to gate oxide. Ruthenium is similarly suited as a diffusion barrier metallization between, e.g., silicon and aluminum and as an interconnection metallization material. And, as a diffusion barrier material, ruthenium dioxide may be used.
    Type: Grant
    Filed: June 3, 1987
    Date of Patent: July 25, 1989
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Martin L. Green, Michal E. Gross
  • Patent number: 4849799
    Abstract: A resonant-tunneling, heterostructure bipolar transistor having a quantum well between emitter contact and collector region is described. In one embodiment, a compositionally graded portion of the emitter region is adjacent to the base region, and there is a double barrier in the base region. In another embodiment the quantum well is defined by the emitter and a potential barrier in the base region. Further embodiments have a quantum well between emitter and collector regions or else within the emitter region.
    Type: Grant
    Filed: August 18, 1986
    Date of Patent: July 18, 1989
    Assignee: American Telephone and Telegraph Company AT&T Bell Laboratories
    Inventors: Federico Capasso, Harry T. French, Arthur C. Gossard, Albert L. Hutchinson, Richard A. Kiehl, Sustana Sen
  • Patent number: 4831628
    Abstract: A method of selective area epitaxial growth using a scanning ion beam is described.
    Type: Grant
    Filed: November 10, 1986
    Date of Patent: May 16, 1989
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventor: Won-Tien Tsang
  • Patent number: 4829349
    Abstract: A transistor device using an interdigitated gate and electrode surface structure to control thermionic emission over a potential barrier is described. Complementary logic structures comprising such transistors are discussed.
    Type: Grant
    Filed: June 30, 1983
    Date of Patent: May 9, 1989
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventor: Sergey Luryi
  • Patent number: 4828358
    Abstract: To facilitate testing in the manufacture, operation, and maintenance of substrate-supported assemblies such as, e.g., optical transmitters and receivers in subscriber-loop and local-area networks, an assembly is provided with built-in optical test features at selected test points. Preferred test features may include side-by-side couplers or reflector taps as may serve to extract or insert light into a substrate-supported waveguide. Testing may further involve the use of a test set having optical components in alignment with test features of an assembly.
    Type: Grant
    Filed: March 3, 1988
    Date of Patent: May 9, 1989
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventor: Greg E. Blonder
  • Patent number: 4826282
    Abstract: A structure of first and second grating sections separated by a phase-shift section serves as a narrow-band resonator filter. Such structure may be optically coupled to a semiconductor laser cavity, and the resulting assembly can serve as a tunable narrow-linewidth laser, e.g., in wavelength-multiplexed and coherent-lightwave communications systems.
    Type: Grant
    Filed: July 21, 1987
    Date of Patent: May 2, 1989
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventor: Rodney C. Alferness
  • Patent number: 4810325
    Abstract: Epitaxial layers are grown from a body of molten material which includes flux and layer constituent components; included in the flux are lead oxide and a small amount of boron trioxide. As compared with prior-art processing in the absence of boron trioxide, enhanced yield is realized as believed to be due to reduced adhesion of solidifying material entrained upon withdrawal of a substrate after growth. The method is particularly useful in the manufacture of magnetic domain devices designed to operate at extreme temperatures, as well as in the manufacture of magneto-optic devices such as, e.g., switches, modulators, and isolators.
    Type: Grant
    Filed: June 15, 1987
    Date of Patent: March 7, 1989
    Assignee: American Telephone and Telegraph Company, AT&T Bell Labs
    Inventor: Steven J. Licht
  • Patent number: 4800051
    Abstract: Low temperature sintering of grade materials sintered to 99 percent of the theoretical density is described using TiO.sub.2 powder prepared by hydrolyzing titanium isopropoxide and calcining at 850.degree. C.
    Type: Grant
    Filed: April 13, 1987
    Date of Patent: January 24, 1989
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventor: Man F. Yan
  • Patent number: 4794440
    Abstract: A heterojunction bipolar transistor having means for changing carrier transport properties is described.
    Type: Grant
    Filed: December 30, 1987
    Date of Patent: December 27, 1988
    Assignee: American Telephone and Telegraph Company, AT&T Bell laboratories
    Inventors: Federico Capasso, Arthur C. Gossard, John R. Hayes, Roger J. Malik, Pierre M. Petroff
  • Patent number: 4791072
    Abstract: Complementary structure implemented in Group III-V compound semiconductors is obtained by using an n-channel field effect transistor and a p-channel MODFET.
    Type: Grant
    Filed: April 7, 1987
    Date of Patent: December 13, 1988
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventor: Richard A. Kiehl
  • Patent number: 4785244
    Abstract: Devices such as, e.g., switches, flowmeters, and proximity sensors, as well as implant devices are made comprising an elongated ferromagnetic element. When the element is exposed to a variable magnetic field an electrical signal is obtained between contact points of the element in response to a change in the magnetic field. Preferred elongated elements have a helically deformed microduplex structure as may be produced by heat treatment and plastic twisting of a body of an alloy such as, e.g., an iron-nickel alloy.
    Type: Grant
    Filed: April 8, 1987
    Date of Patent: November 15, 1988
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Sungho Jin, Richard C. Sherwood, Thomas H. Tiefel, Robert B. van Dover
  • Patent number: 4772866
    Abstract: A structure of alternating layers of titanium and an insulator or semiconductor material has temperature-sensitive electrical resistivity. In combination with a resistance-measuring circuit, such structure can serve as an accurate temperature sensor. And, since electrical resistivity is inversely related to temperature, disclosed structures can serve as miniature thermistors in integrated circuit devices.
    Type: Grant
    Filed: April 11, 1986
    Date of Patent: September 20, 1988
    Inventor: Ronald H. Willens
  • Patent number: 4772924
    Abstract: A strained layer superlattice comprising Ge.sub.x Si.sub.1-x layers interleaved with Si layers is an excellent photodetector at infrared wavelengths due to the large shift in bandgap caused by the strain in the superlattice.
    Type: Grant
    Filed: November 25, 1987
    Date of Patent: September 20, 1988
    Inventors: John C. Bean, David V. Lang, Thomas P. Pearsall, Roosevelt People, Henryk Temkin
  • Patent number: 4770494
    Abstract: Certain dopant materials, when present in a significant power-carrying portion of a silica-based optical waveguide fiber, are effective as intrinsic loss-reducing agents; the concentration of such dopant materials is at significantly lower levels as compared with levels used for producing a refractive index difference. Suitable in this respect are germania and phosphorus pentoxide as added to essentially pure silica or to silica containing other dopant additives such as, e.g., alumina or fluorine as may be used in a waveguiding core-cladding structure. Intrinsic loss in the vicinity of 0.2 dB/km is readily realized.
    Type: Grant
    Filed: February 12, 1986
    Date of Patent: September 13, 1988
    Assignee: American Telephone & Telegraph Company, AT&T Bell Laboratories
    Inventors: Roseann Csencsits, Paul J. Lemaire, Katherine T. Nelson, Kenneth L. Walker
  • Patent number: 4765706
    Abstract: Low-loss coupling between a local feed connection or node, and a multi-mode optical fiber bus is provided by reflective insertion of a relatively small number of modes into the bus fiber. Essentially all input power available at the node is thus inserted into the bus, while but a small portion of power is extracted from the bus.
    Type: Grant
    Filed: July 29, 1986
    Date of Patent: August 23, 1988
    Assignee: American Telephone and Telegraph Co., AT&T Bell Labs.
    Inventors: Enrique A. J. Marcatili, Thomas H. Wood
  • Patent number: 4740987
    Abstract: A distributed-feedback laser includes in its grating a localized phase-slip discontinuity which is placed off-center. Such discontinuity results in a quarter-wave phase slip, and it can be placed, e.g., such as to maximize the difference between threshold gain of the lowest-lasing mode and cavity loss of the next-to-lowest-lasing mode. The invention is applicable especially where laser output intensity differs at two output facets and results in enhanced mode selectivity during laser operation.
    Type: Grant
    Filed: June 30, 1986
    Date of Patent: April 26, 1988
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Samuel L. McCall, Jr., Philip M. Platzman
  • Patent number: 4739385
    Abstract: A modulation-doped field effect photodetector has a fast response time.
    Type: Grant
    Filed: January 12, 1987
    Date of Patent: April 19, 1988
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Clyde G. Bethea, Chung Y. Chen, Alfred Y. Cho
  • Patent number: 4737233
    Abstract: Semiconductor crystal films on a dielectric substrate are advantageously made by a zone melting method. Single-crystal structure is initiated at a seed surface, and made to extend across a dielectric surface by melting and resolidifying.Melting is effected upon irradiation with optical radiation which is focused onto an elongated zone; the zone is moved so as to locally melt successive portions of a layer of precursor material which may be amorphous or polycrystalline. The use of incoherent radiation is convenient, and focusing is typically by using a reflector.The process is conveniently effected under a controlled atmosphere and the layer being crystallized may be encapsulated so that no free semiconductor surface is exposed to an atmosphere.
    Type: Grant
    Filed: September 2, 1986
    Date of Patent: April 12, 1988
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Avid Kamgar, Ernest Labate, Joseph R. Ligenza, Simon M. Sze
  • Patent number: 4737112
    Abstract: Electrical interconnection is established by means of an anisotropically conductive, composite layer medium comprising electrically conductive particles in a nonconductive matrix material. Enhanced uniformity of conductivity across the medium, and minimized incidence of lateral shorting are achieved as a result of essentially uniform distribution of electrically conductive particles which are also magnetic, such distribution resulting upon application of a magnetic field essentially perpendicular to a layer before or during hardening of the matrix material.
    Type: Grant
    Filed: September 5, 1986
    Date of Patent: April 12, 1988
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Sungho Jin, John J. Mottine, Jr., Stephen G. Seger, Jr., Richard C. Sherwood, Thomas H. Tiefel