With Particular Contact Geometry (e.g., Ring Or Grid) Patents (Class 257/457)
  • Patent number: 5525828
    Abstract: Silicon-VLSI-compatible photodetectors, in the form of a metal-semiconductor-metal photodetector (MSM-PD) or a lateral p-i-n photodetector (LPIN-PD), are disclosed embodying interdigitated metallic electrodes on a silicon surface. The electrodes of the MSM-PD have a moderate to high electron and hole barrier height to silicon, for forming the Schottky barriers, and are fabricated so as to be recessed in the surface semiconducting layer of silicon through the use of self-aligned metallization either by selective deposition or by selective reaction and etching, in a manner similar to the SALICIDE concept. Fabrication is begun by coating the exposed Si surface of a substrate with a transparent oxide film, such that the Si/oxide interface exhibits low surface recombination velocity.
    Type: Grant
    Filed: August 23, 1994
    Date of Patent: June 11, 1996
    Assignee: International Business Machines Corporation
    Inventors: Ernest Bassous, Jean-Marc Halbout, Subramanian S. Iyer, Rajiv V. Joshi, Vijay P. Kesan, Michael R. Scheuermann, Massimo A. Ghioni
  • Patent number: 5523610
    Abstract: A photodiode array is provided which includes a cell comprised of at least a substrate, an insulating film formed on the substrate, a semiconductor layer containing an impurity of first conductivity type and provided on the insulating film, an impurity-diffusion layer of second conductivity type formed in the semiconductor layer and reaching the insulating film, and at least one impurity-diffusion layer of the first conductivity type formed within the impurity-diffusion layer of the second conductivity type and reaching the insulating film, wherein pn junctions are defined between the layers of opposite conductivity types and arranged laterally, and of the pn junctions, any pn junction of a predetermined order are connected to each other in series. By virtue of this arrangement, the area of pn junctions per unit area of a substrate is increased thereby contributing to a reduction in chip size and in production cost.
    Type: Grant
    Filed: July 7, 1994
    Date of Patent: June 4, 1996
    Assignee: Rohm Co., Ltd.
    Inventors: Koichi Kudo, Yasuo Aki
  • Patent number: 5512763
    Abstract: A metal-semiconductor-metal (MSM) device comprises interdigitated metal electrodes (2, 3) on a semiconductor substrate (1). When embodied as a photoconductor, a photoconductive region (4) is bounded by layers (5, 6) which form a resonant cavity for incoming radiation to improve the response. In another embodiment, which can be either a photodiode or photoconductor, the electrodes are arranged to extend into the thickness of the photoresponsive layer (4). To reduce sensitivity to polarization,the electrodes may be arranged in sets extending in mutually transverse directions. Groups of the electrodes may be connected so as to be sensitive to polarization but substantially insensitive to the amplitude of incoming radiation.
    Type: Grant
    Filed: October 11, 1994
    Date of Patent: April 30, 1996
    Assignee: Hitachi, Ltd.
    Inventor: Jeremy Allam
  • Patent number: 5461246
    Abstract: A metal-semiconductor-metal (MSM) photodetector in a silicon substrate. An insulating layer overlies the silicon substrate. An active layer is carried on the insulating layer and is separated from the silicon substrate. The active layer has an active layer thickness. Interdigitated fingers are carried on the active layer. The interdigitated fingers develop a potential therebetween related to incident radiation. Spacing between the interdigitated fingers is related to thickness of the active layer.
    Type: Grant
    Filed: May 12, 1994
    Date of Patent: October 24, 1995
    Assignee: Regents of the University of Minnesota
    Inventor: Stephen Y. Chou
  • Patent number: 5451769
    Abstract: A high speed, metal-semiconductor-metal photodetector includes a pair of generally circular, electrically conductive electrodes formed on an optically active semiconductor layer. Various embodiments of the invention include a spiral, intercoiled electrode geometry and an electrode geometry having substantially circular, concentric electrodes which are interposed. These electrode geometries result in photodetectors with lower capacitances, dark currents and lower inductance which reduces the ringing seen in the optical pulse response.
    Type: Grant
    Filed: January 5, 1994
    Date of Patent: September 19, 1995
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: James A. McAdoo, Elias Towe, William L. Bishop, Liang-Guo Wang
  • Patent number: 5306943
    Abstract: A Schottky barrier diode includes a semiconductor substrate, an ohmic electrode formed on a first region of the semiconductor substrate, and a Schottky metal electrode formed on a second region spaced apart from the first region on the semiconductor substrate. The Schottky electrode includes at least one ohmic portion forming an ohmic contact with the semiconductor substrate, whereby rectifying characteristics of the Schottky barrier diode are improved.
    Type: Grant
    Filed: March 30, 1992
    Date of Patent: April 26, 1994
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Hisashi Ariyoshi, Masaaki Sueyoshi, Kouichi Sakamoto, Susumu Fukuda
  • Patent number: 5285098
    Abstract: A method and structure are provided for internal photoemission detection. At least one groove (30a) is formed in a side of a semiconductor layer (32). A silicide film (58) is formed in each groove (30a) over the semiconductor layer (32). A metal contact region (44) is electrically coupled to the silicide film (58) such that a voltage at the metal contact region (44) indicates an intensity of radiation incident on the structure (28).
    Type: Grant
    Filed: April 30, 1992
    Date of Patent: February 8, 1994
    Assignee: Texas Instruments Incorporated
    Inventor: Sebastian R. Borrello
  • Patent number: 5248347
    Abstract: In a semiconductor device having a metal electrode on a crystalline semiconductor surface, the metal electrode includes first portions electrically and mechanically connected to the surface and second portions mechanically separated from the surface and having configurations that easily deform. These first and second portions are alternatingly arranged on the surface. Accordingly, stress applied to the semiconductor beneath the electrode is reduced and deformation of the semiconductor element due to thermal stress is prevented, thereby preventing deterioration of element characteristics.
    Type: Grant
    Filed: February 6, 1992
    Date of Patent: September 28, 1993
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Seiji Ochi
  • Patent number: 5212395
    Abstract: This invention pertains to a p-i-n In.sub.0.53 Ga.sub.0.47 As photodiode having an optically transparent composite top electrode consisting of a thin semitransparent metal layer from 10 to 40 nm thick and a transparent cadmium tin oxide (CTO) layer from 90 to 600 nm thick. The metal layer makes a non-alloyed ohmic contact to the semiconductor surface, acts as a barrier between the semiconductor and the CTO preventing oxidation of the semiconductor from the O.sub.2 in the plasma during reactive magnetron sputtering of the CTO layer, and prevents formation of a p-n junction between the semiconductor and CTO. The CTO functions as the n or p contact, an optical window and an anti-reflection coating. The top electrode also avoids shadowing of the active layer by the top electrode, thus allowing greater collection of incident light. Since the top electrode is non-alloyed, inter-diffusion into the i-region is not relevant, which avoids an increased dark current.
    Type: Grant
    Filed: March 2, 1992
    Date of Patent: May 18, 1993
    Assignee: AT&T Bell Laboratories
    Inventors: Paul R. Berger, Alfred Y. Cho, Niloy K. Dutta, John Lopata, Henry M. O'Bryan, Jr., Deborah L. Sivco, George J. Zydzik