Polycrystalline Patents (Class 148/DIG122)
  • Patent number: 4769338
    Abstract: There is disclosed a film field effect transistor which can be operated at fast switching rates for use, for example, in video display applications. The transistor includes a body of silicon semiconductor material having a structure more ordered than amorphous material and less ordered than single crystalline material. The source and drain of the transistor comprise rectifying contacts formed on the body of silicon semiconductor material. Also disclosed are a method of making the transistor and an electronically addressable array system utilizing the transistor to advantage.
    Type: Grant
    Filed: March 9, 1987
    Date of Patent: September 6, 1988
    Assignee: Energy Conversion Devices, Inc.
    Inventors: Stanford R. Ovshinsky, Stephen J. Hudgens
  • Patent number: 4766477
    Abstract: A semiconductor device mainly comprises a semiconductor layer of a polycrystalline silicon film containing at least one atom selected from the group consisting of carbon, sulfur, nitrogen and oxygen as a constituent.
    Type: Grant
    Filed: July 11, 1986
    Date of Patent: August 23, 1988
    Assignee: Canon Kabushiki Kaisha
    Inventors: Katsumi Nakagawa, Toshiyuki Komatsu, Yoshiyuki Osada, Satoshi Omata, Yutaka Hirai, Takashi Nakagiri
  • Patent number: 4762807
    Abstract: An insulated-gate field effect transistor (IGFET) having the structure of the source and drain disposed in the longitudinal direction, i.e., the laminating direction, so that the channel region extends in the lateral direction when a high voltage is applied. This structure prevents a high current density at the interface of the channel region and the gate insulation film, allowing the fabrication of a large-current power transistor or the integration of such transistors.
    Type: Grant
    Filed: August 13, 1986
    Date of Patent: August 9, 1988
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Shunpei Yamazaki
  • Patent number: 4755484
    Abstract: A semiconductor contact system controls the boundary recombination velocity and optimizes the semiconductor transport phenomena and includes a microcrystalline layer of doped semiconductor microcrystals surrounded by a semiconductor oxide. The microcrystalline layer is acceptor and oxygen doped to provide unipolar hole transport and donor and oxygen doped to provided unipolar electron transport. The oxygen doping is implanted several atomic layers into the semiconductor to form a gradient between the semiconductor and microcrystalline layer to preserve the semiconductor monocrystalline lattice. The thickness of the microcrystalline film is adjusted to be thick enough to control the effective chemostatic potential terminating the semiconductor and thin enough to enhance the series microcrystalline film resistance.
    Type: Grant
    Filed: June 19, 1986
    Date of Patent: July 5, 1988
    Assignee: Texas Instruments Incorporated
    Inventor: Patrick A. Curran
  • Patent number: 4724220
    Abstract: The fabrication of high performance and reliable Buried Channel Field Effect Transistor (BCFET) using Schottky gate junction and heavily doped N layers for the source and drain electrode is described. The BCFET is composed of a semi-insulating substrate in which two N layers for the drain electrodes and one N layer for the source electrode are formed in one of the semi-insulating surface. The N source electrode is centrally located between the two N electrodes and all three lie in the same plane. The source and drain electrodes are separated by a thin semi-insulating layer, the length of which can range from 0.5 micron to several micron range, depending on the desired voltage breakdown. A Schottky gate is defined in an active N layer directly above the source N layer. The ohmic contacts for the source and drain N layers are defined several microns away from the Schottky junction, resulting in a considerable improvement in device reliability.
    Type: Grant
    Filed: January 10, 1986
    Date of Patent: February 9, 1988
    Assignee: Eaton Corporation
    Inventor: Joseph A. Calviello
  • Patent number: 4702000
    Abstract: The problem of unwanted residual polysilicon stringers along the sidewalls of a field oxide layer employed in direct moat wafer processing is avoided by a processing scheme in which the sidewalls of the aperture in the field oxide layer are initially tapered prior to formation of the polysilicon layer to be used for the gate electrode(s). Because of the graduated thickness of the sidewalls of the field oxide layer, the thickness of the polysilicon layer formed thereon is substantially uniform over the entirety of the substrate. As a result, during subsequent masking of the polysilicon layer to define the gate electrode(s), all unmasked portions of the polysilicon are completely etched, leaving no residual material (e.g. stringers) that could be a source of device contamination.
    Type: Grant
    Filed: March 19, 1986
    Date of Patent: October 27, 1987
    Assignee: Harris Corporation
    Inventors: Dyer A. Matlock, Richard L. Lichtel, Jr., Lawrence G. Pearce
  • Patent number: 4680614
    Abstract: A void-free isolated semiconductor substrate is described which contains a pattern of substantially vertically sided trenches within a semiconductor body. The pattern of isolation trenches isolate regions of monocrystalline semiconductor material which may contain active and passive semiconductor devices. A first insulating layer is located upon the sidewalls of the trenches. The base or bottom of the trenches is open to the monocrystalline semiconductor body. An epitaxial layer extending from the base of the trenches fills the pattern of trenches up to a level from the upper surface of the trenches as specified approximately by the equation:y=0.34xwhere y is the distance between the epitaxial layer and the top surface and x is the trench width. The preferred range for the trench width x is about 10 micrometers or less. A polycrystalline silicon layer fills the additional portion of the pattern of trenches above the upper surfaces of the epitaxial layer.
    Type: Grant
    Filed: March 14, 1985
    Date of Patent: July 14, 1987
    Inventors: Klaus D. Beyer, Victor J. Silvestri
  • Patent number: 4649630
    Abstract: A process is disclosed for controllably providing dielectrically isolated semiconductor regions having a uniform and well defined thickness. Grooves are formed in a first surface of a semiconductor substrate and then a dielectric layer is formed covering that surface and the grooves extending into the surface. A layer of backing material such as polycrystalline silicon is formed overlying the dielectric layer. A semiconductor substrate is then thinned to form a new surface with portions of the dielectric layer and backing material exposed at that surface. A semiconductor layer is epitaxially grown overlying the new surface with the semiconductor layer having a monocrystalline structure where it is grown on exposed regions of the original substrate and having a polycrystalline structure otherwise. An oxidation masking layer is formed overlying those portions of the semiconductor layer which have a monocrystalline structure.
    Type: Grant
    Filed: April 1, 1985
    Date of Patent: March 17, 1987
    Assignee: Motorola, Inc.
    Inventors: Bernard W. Boland, Paul W. Sanders
  • Patent number: 4649638
    Abstract: A construction process employs an insulating abutment which serves as a guide in the formation of a shortlength electrode in the fabrication of a semiconductor device. The process is particularly useful in construction of extremely short channel asymmetric lightly doped drain (LDD) silicon FET's in which case a bird beak is formed on the surface of a silicon wafer. The bird beak is composed of silicon dioxide produced by oxidation of the silicon substrate with the aid of an oxidation resistant covering of silicon nitride, the edge of which defines the location of the abutment. Reactive ion etching is employed to remove excess silicon dioxide leaving a vertical wall at one side of the abutment. Thereafter, the silicon nitride layer is stripped off leaving a slating roof to the abutment. A dope polysilicon layer is deposited conformally on the surface of the substrate and on the abutment to a depth equal to the desired length of the electrode.
    Type: Grant
    Filed: April 17, 1985
    Date of Patent: March 17, 1987
    Assignee: International Business Machines Corp.
    Inventors: Frank F. Fang, Bertrand M. Grossman
  • Patent number: 4646427
    Abstract: In a method of electrically altering the characteristics of a semiconductor device, a lateral polysilicon zener diode's zener knee voltage may be shifted either to a higher or lower voltage. An electrical potential may be applied in the forward direction to shift the zener knee to a higher voltage level. An electrical potential may be applied in the reverse bias direction to shift the zener knee to a lower voltage. In the limit, the zener may be changed into a forward diode of reverse polarity with respect to the original zener. The electrical potential used should be of appropriate magnitude to melt the polysilicon without damage to the zener's terminals. This induces migration of the impurities causing a rediffusion of impurities thereby altering the characteristics of the diode. This method may be used to program a PROM by either converting the zener to a diode or not to program each binary bit.
    Type: Grant
    Filed: June 28, 1984
    Date of Patent: March 3, 1987
    Assignee: Motorola, Inc.
    Inventor: James T. Doyle
  • Patent number: 4631804
    Abstract: A technique is disclosed for the artificial introduction of a localized subsurface strained layer within a thick polysilicon layer to minimize the large change in warpage (defined as springback) which occurs in a (100) Si substrate thinning operation during the mechanical processing of dielectrically isolated (DI) wafers. This novel technique is capable of favorably altering the state of stress and the stress profile in the multicomponent "polysilicon/SiO.sub.2 /(100) Si" DI structure so as to reduce the natural springback in warpage that occurs when the stiffening member, the (100) Si substrate, is removed. This subsurface disturbed layer is retained within the polysilicon layer during subsequent processing to maintain the favorable stress profile with a minimum of wafer warpage. In one embodiment of the present invention, the subsurface strained layer is generated by growing an interface layer (SiO.sub.2 or Si.sub.3 N.sub.
    Type: Grant
    Filed: December 10, 1984
    Date of Patent: December 30, 1986
    Assignee: AT&T Bell Laboratories
    Inventor: Pradip K. Roy
  • Patent number: 4625391
    Abstract: A method of forming electric conductive patterns comprising the steps of forming first conductive patterns on a semiconductor substrate directly or through an insulating layer with first insulating film being formed thereon, selectively forming second conductive patterns, forming insulation layers on side surfaces of said second conductive patterns, thereby electrically insulating said second conductive patterns from said first conductive patterns through said insulation layers in a self-aligned manner. An semiconductor device having electric conductive patterns formed by above-mentioned method.
    Type: Grant
    Filed: June 18, 1982
    Date of Patent: December 2, 1986
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventor: Yoshitaka Sasaki
  • Patent number: 4601096
    Abstract: The fabrication of high performance and reliable Buried Channel Field Effect Transistor (BCFET) using Schottky gate junction and heavily doped N layers for the source and drain electrode is described. The BCFET is composed of a semi-insulating substrate in which two N layers for the drain electrodes and one N layer for the source electrode are formed in one of the semi-insulating surface. The N source electrode is centrally located between the two N drain electrodes and all three lie in the same plane. The source and drain electrodes are separated by a thin semi-insulating layer, the length of which can range from 0.5 micron to several micron range, depending on the desired voltage breakdown. A Schottky gate is defined in an active N layer directly above the source N layer. The ohmic contacts for the source and drain N layers are defined several mcirons away from the Schottky junction, resulting in a considerable improvement in device reliability.
    Type: Grant
    Filed: February 19, 1985
    Date of Patent: July 22, 1986
    Assignee: Eaton Corporation
    Inventor: Joseph A. Calviello
  • Patent number: 4587547
    Abstract: An electrode structure for use in semiconductor devices comprising: a semiconductive layer; a conductive layer disposed on one surface of the semiconductive layer; first regions which intervene between the layers and serve as passages for transmitting minority carriers from the semiconductive layer to said conductive layer; and second regions which intervene between said layers and serve as passages for conveying majority carriers between the semiconductive layer and conductive layer, the first and second regions being selectively formed on the semiconductive layer so as to be adjacent to one another.
    Type: Grant
    Filed: July 12, 1983
    Date of Patent: May 6, 1986
    Assignee: Nippon Telegraph & Telephone Public Corp.
    Inventors: Yoshihito Amemiya, Takayuki Sugeta, Yoshihiko Mizushima
  • Patent number: 4581814
    Abstract: The efficacy of dielectrically isolated device formation on a substrate is substantially enhanced through a specific set of processing steps. In particular, before silicon oxide regions, e.g., gate oxide regions, are produced, bulk polycrystalline areas are heat treated to substantially increase their polycrystalline silicon grain size.
    Type: Grant
    Filed: December 13, 1984
    Date of Patent: April 15, 1986
    Assignee: AT&T Bell Laboratories
    Inventors: George K. Celler, Pradip K. Roy, Donald G. Schimmel, Lee E. Trimble
  • Patent number: 4574469
    Abstract: A process is described for producing isolated semiconductor devices in a common substrate which have self-aligned and pre-located isolation walls, buried layers, and channel-stops. The isolation walls are formed from a stacked arrangement of a dielectric region and a non-single crystal semiconductor region, above a doped channel-stop region. A single mask layer determines the location and spacing of the non-single crystal portion of the isolation walls, the channel-stops, and the buried layers.
    Type: Grant
    Filed: September 14, 1984
    Date of Patent: March 11, 1986
    Assignee: Motorola, Inc.
    Inventors: Sal Mastroianni, Carroll Casteel, Terry S. Hulseweh
  • Patent number: 4573257
    Abstract: A process is described for fabricating self-aligned buried doped regions in semiconductor devices and integrated circuits which avoids any need for delineation of the buried doped regions in the active portions of the device. Avoiding delineation improves the quality of the epitaxial layer used to cover the buried doped regions thereby improving overall performance and yield. Multiple mask layers are used in connection with a single mask pattern to achieve self-alignment. One mask layer consists of a material with a modifiable etch rate, e.g. polysilicon. A portion of the single crystal substrate is rendered non-single crystal and used as an alignment key which is propagated through the epitaxial layer grown over the undelineated buried doped regions. The dimensions and separations of the self-aligned buried doped regions can be precisely controlled.
    Type: Grant
    Filed: September 14, 1984
    Date of Patent: March 4, 1986
    Assignee: Motorola, Inc.
    Inventor: Terry S. Hulseweh
  • Patent number: 4567646
    Abstract: A method for fabricating a wafer for a dielectric isolation (DI) integrated circuit device is provided, wherein the substrate of the wafer, comprises portions of polycrystalline silicon positioned beneath regions for electrical elements, namely, "islands", and portions of single crystal silicon are positioned in other areas of the wafer such as scribing regions, peripheral regions and contact regions. The single crystal portions of the substrate are grown during its fabricating steps by exposing surfaces of an original substrate of single crystal silicon, before the deposition of silicon onto the original substrate, by removing a dielectric isolation layer over the predetermined regions to be exposed. The single crystal silicon portions of the wafer provide various advantages for subsequent mechanical processing of the wafer such as shaping and rounding of the peripheral region and the scribing of the wafer into dice.
    Type: Grant
    Filed: November 30, 1984
    Date of Patent: February 4, 1986
    Assignee: Fujitsu Limited
    Inventors: Tamotsu Ishikawa, Hirokazu Tanaka, Akira Tabata