Multistep Processes For Manufacture Of Device Whose Active Layer, E.g., Base, Channel, Comprises Silicon Carbide (epo) Patents (Class 257/E21.065)
  • Patent number: 7763529
    Abstract: A method of fabricating a silicon carbide (SiC) layer is disclosed, which comprises steps: (S1) heating a silicon-based substrate at a temperature of X ° C.; (S2) carburizating the silicon-based substrate with a first hydrocarbon-containing gas at a temperature of Y ° C. to form a carbide layer on the silicon-based substrate; (S3) annealing the silicon-based substrate with the carbide layer thereon at a temperature of Z ° C.; and (S4) forming a silicon carbide layer on the carbide layer with a second hydrocarbon-containing gas and a silicon-containing gas at a temperature of W ° C.; wherein, X is 800 to 1200; Y is 1100 to 1400; Z is 1200 to 1500; W is 1300 to 1550; and X<Y?Z?W. In the method of the present invention, since no cooling steps between respective steps are required, the full process time can be reduced and the cost is lowered because no energy consumption occurs for the cooling and the re-heating steps.
    Type: Grant
    Filed: September 25, 2009
    Date of Patent: July 27, 2010
    Assignee: National Tsing Hua University
    Inventors: Wei-Yu Chen, Jenn-Chang Hwang, Chih-Fang Huang, Chien-Cheng Chen
  • Publication number: 20100155743
    Abstract: One aspect includes a semiconductor device with self-aligned contacts, integrated circuit and manufacturing method. One embodiment provides gate control structures. Each of the gate control structures is configured to control the conductivity of a channel region within a silicon carbide substrate by field effect. A contact hole is self-aligned to opposing sidewalls of adjacent gate control structures by intermediate spacers.
    Type: Application
    Filed: December 22, 2008
    Publication date: June 24, 2010
    Applicant: INFINEON TECHNOLOGIES AUSTRIA AG
    Inventors: Michael Treu, Kathrin Rueschenschmidt, Oliver Haeberlen, Franz Auerbach
  • Publication number: 20100133550
    Abstract: A silicon carbide-based power device includes a silicon carbide drift layer having a planar surface that forms an off-axis angle with a <0001> direction of less than 8°.
    Type: Application
    Filed: November 20, 2009
    Publication date: June 3, 2010
    Inventors: Qingchun Zhang, Anant Agarwal, Doyle Craig Capell, Albert Burk, Joseph Sumakeris, Michael O'Loughlin
  • Patent number: 7713805
    Abstract: A method of manufacturing a silicon carbide semiconductor device having a MOS structure includes preparing a substrate made of silicon carbide, and forming a channel region, a first impurity region, a second impurity region, a gate insulation layer, and a gate electrode to form a semiconductor element on the substrate. In addition, a film is formed on the semiconductor element to provide a material of an interlayer insulation layer, and a reflow process is performed at a temperature about 700° C. or over in an wet atmosphere so that the interlayer insulation layer is formed from the film and an edge portion of the gate electrode is rounded and oxidized.
    Type: Grant
    Filed: October 23, 2007
    Date of Patent: May 11, 2010
    Assignee: DENSO CORPORATION
    Inventors: Hiroki Nakamura, Hiroyuki Ichikawa, Eiichi Okuno
  • Publication number: 20100081261
    Abstract: A method of fabricating a silicon carbide (SiC) layer is disclosed, which comprises steps: (S1) heating a silicon-based substrate at a temperature of X ° C.; (S2) carburizating the silicon-based substrate with a first hydrocarbon-containing gas at a temperature of Y ° C. to form a carbide layer on the silicon-based substrate; (S3) annealing the silicon-based substrate with the carbide layer thereon at a temperature of Z ° C.; and (S4) forming a silicon carbide layer on the carbide layer with a second hydrocarbon-containing gas and a silicon-containing gas at a temperature of W ° C.; wherein, X is 800 to 1200; Y is 1100 to 1400; Z is 1200 to 1500; W is 1300 to 1550; and X<Y?Z?W. In the method of the present invention, since no cooling steps between respective steps are required, the full process time can be reduced and the cost is lowered because no energy consumption occurs for the cooling and the re-heating steps.
    Type: Application
    Filed: September 25, 2009
    Publication date: April 1, 2010
    Applicant: National Tsing Hua University
    Inventors: Wei-Yu Chen, Jenn-Chang Hwang, Chih-Fang Huang, Chien-Cheng Chen
  • Patent number: 7675068
    Abstract: A silicon carbide structure is disclosed that is suitable for use as a substrate in the manufacture of electronic devices such as light emitting diodes. The structure includes a silicon carbide wafer having a first and second surface and having a predetermined conductivity type and an initial carrier concentration; a region of implanted dopant atoms extending from the first surface into the silicon carbide wafer to a predetermined depth, with the region having a higher carrier concentration than the initial carrier concentration in the remainder of the wafer; and an epitaxial layer on the first surface of the silicon carbide wafer.
    Type: Grant
    Filed: October 5, 2005
    Date of Patent: March 9, 2010
    Assignee: Cree, Inc.
    Inventors: Davis Andrew McClure, Alexander Suvorov, John Adam Edmond, David Beardsley Slater, Jr.
  • Publication number: 20100035411
    Abstract: A method of manufacturing an SiC semiconductor device includes the steps of ion implanting a dopant at least in a part of a surface of an SiC single crystal, forming an Si film on the surface of the ion-implanted SiC single crystal, and heating the SiC single crystal on which the Si film is formed to a temperature not less than a melting temperature of the Si film.
    Type: Application
    Filed: August 13, 2007
    Publication date: February 11, 2010
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Kazuhiro Fujikawa, Takeyoshi Masuda
  • Patent number: 7622741
    Abstract: A semiconductor device of a double diffused MOS structure employing a silicon carbide semiconductor substrate. The semiconductor device comprises a silicon carbide semiconductor epitaxial layer provided on a surface of the silicon carbide semiconductor substrate and having a first conductivity which is the same conductivity as the silicon carbide semiconductor substrate, and an impurity region formed by doping a surface portion of the silicon carbide semiconductor epitaxial layer with an impurity of a second conductivity, the impurity region having a profile such that a near surface thereof has a relatively low second-conductivity impurity concentration and a deep portion thereof has a relatively high second-conductivity impurity concentration.
    Type: Grant
    Filed: February 25, 2005
    Date of Patent: November 24, 2009
    Assignee: Rohm Co., Ltd.
    Inventor: Mineo Miura
  • Publication number: 20090230404
    Abstract: MOSFET (30) is provided with SiC film (11). SiC film (11) has a facet on its surface, and the length of one period of the facet is 100 nm or more, and the facet is used as channel (16). Further, a manufacturing method of MOSFET (30) includes: a step of forming SiC film (11); a heat treatment step of heat-treating SiC film (11) in a state where Si is supplied on the surface of SiC film (11); and a step of forming the facet obtained on the surface of SiC film (11) by the heat treatment step into a channel (16). Thereby, it is possible to sufficiently improve the characteristics.
    Type: Application
    Filed: October 26, 2006
    Publication date: September 17, 2009
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Takeyoshi Masuda, Shinji Matsukawa
  • Patent number: 7488984
    Abstract: Doped silicon carbide structures, as well as methods associated with the same, are provided. The structures, for example, are components (e.g., layer, patterned structure) in MEMS structures. The doped silicon carbide structures may be highly conductive, thus, providing low resistance to electrical current. An in-situ doping process may be used to form the structures. The process parameters can be selected so that the structures have a low residual stress and/or low strain gradient. Thus, the structures may be formed having desired dimensions with little (or no) distortion arising from residual stress and/or strain gradient. The high conductivity and mechanical integrity of the structures are significant advantages in MEMS devices such as sensors and actuators.
    Type: Grant
    Filed: April 19, 2006
    Date of Patent: February 10, 2009
    Assignee: FLX Micro, Inc.
    Inventors: Jeffrey M. Melzak, Chien-Hung Wu
  • Patent number: 7482068
    Abstract: A uniform silicon carbide single crystal with either an n-type or a p-type conductivity. The crystal has a net carrier concentration less than 1015 cm?3 and a carrier lifetime of at least 50 ns at room temperature.
    Type: Grant
    Filed: August 22, 2003
    Date of Patent: January 27, 2009
    Assignees: Norstel AB, SiCED Electronics Development GmbH & Co. KG
    Inventors: Alexandre Ellison, Björn Magnusson, Asko Vehanen, Dietrich Stephani, Heinz Mitlehner, Peter Friedrichs
  • Patent number: 7479658
    Abstract: A technique for suppressing the bowing of an epitaxial wafer is provided. The epitaxial wafer is prepared by successively epitaxially growing a target group III-nitride layer, an interlayer and another group III-nitride layer on a substrate with a buffer layer. The interlayer is mainly composed of a mixed crystal of GaN and InN expressed in a general formula (GaxIny)N (0?x?1, 0?y?1, x+y=1) (or a crystal of GaN), and does not contain Al. The interlayer is epitaxially formed at a lower growth temperature than those of the group III-nitride layers, more specifically at a temperature in a range of at least 350° C. to not more than 1000° C.
    Type: Grant
    Filed: August 2, 2004
    Date of Patent: January 20, 2009
    Assignee: NGK Insulators, Ltd.
    Inventors: Masahiro Sakai, Mitsuhiro Tanaka, Takashi Egawa
  • Publication number: 20080290371
    Abstract: A semiconductor structure includes a Group III-nitride semiconductor layer, a protective layer on the semiconductor layer, a distribution of implanted dopants within the semiconductor layer, and an ohmic contact extending through the protective layer to the semiconductor layer.
    Type: Application
    Filed: August 5, 2008
    Publication date: November 27, 2008
    Inventors: Scott T. Sheppard, Adam Saxler
  • Patent number: 7439594
    Abstract: A stacked non-volatile memory device uses amorphous silicon based thin film transistors stacked vertically. Each layer of transistors or cells is formed from a deposited a-Si channel region layer having a predetermined concentration of carbon to form a carbon rich silicon film or silicon carbide film, depending on the carbon content. The dielectric stack is formed over the channel region layer. In one embodiment, the dielectric stack is an ONO structure. The control gate is formed over the dielectric stack. This structure is repeated vertically to form the stacked structure. In one embodiment, the carbon content of the channel region layer is reduced for each subsequently formed layer.
    Type: Grant
    Filed: March 16, 2006
    Date of Patent: October 21, 2008
    Assignee: Micron Technology, Inc.
    Inventor: Chandra Mouli
  • Patent number: 7411218
    Abstract: A Schottky barrier silicon carbide device has a Re Schottky metal contact. The Re contact 27 is thicker than 250 Angstroms and may be between 2000 and 4000 Angstroms. A termination structure is provided by ion milling an annular region around the Schottky contact.
    Type: Grant
    Filed: March 18, 2005
    Date of Patent: August 12, 2008
    Assignee: Fairchild Semiconductor Corporation
    Inventors: William F. Seng, Richard L. Woodin, Carl Anthony Witt
  • Publication number: 20080102585
    Abstract: A method of manufacturing a silicon carbide semiconductor device having a MOS structure includes preparing a substrate made of silicon carbide, and forming a channel region, a first impurity region, a second impurity region, a gate insulation layer, and a gate electrode to form a semiconductor element on the substrate. In addition, a film is formed on the semiconductor element to provide a material of an interlayer insulation layer, and a reflow process is performed at a temperature about 700° C. or over in an wet atmosphere so that the interlayer insulation layer is formed from the film. Furthermore, a dehydration process is performed at about 700° C. or lower in an inert gas atmosphere after the reflow process is performed.
    Type: Application
    Filed: October 23, 2007
    Publication date: May 1, 2008
    Applicant: DENSO CORPORATION
    Inventors: Hiroki Nakamura, Hiroyuki Ichikawa, Eiichi Okuno
  • Patent number: 7285465
    Abstract: A semiconductor device and its manufacturing method are provided in which the trade-off relation between channel resistance and JFET resistance, an obstacle to device miniaturization, is improved and the same mask is used to form a source region and a base region by ion implantation. In a vertical MOSFET that uses SiC, a source region and a base region are formed by ion implantation using the same tapered mask to give the base region a tapered shape. The taper angle of the tapered mask is set to 30° to 60° when the material of the tapered mask has the same range as SiC in ion implantation, and to 20° to 45° when the material of the tapered mask is SiO2.
    Type: Grant
    Filed: February 15, 2006
    Date of Patent: October 23, 2007
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoichiro Tarui, Ken-ichi Ohtsuka, Masayuki Imaizumi, Hiroshi Sugimoto, Tetsuya Takami
  • Publication number: 20070235757
    Abstract: Bipolar junction transistors (BJTs) are provided including silicon carbide (SiC) substrates. An epitaxial SiC base region is provided on the SiC substrate. The epitaxial SiC base region has a first conductivity type. An epitaxial SiC emitter region is also provided on the SiC substrate. The epitaxial SiC emitter region has a second conductivity type, different from the first conductivity type. The epitaxial SiC emitter region has first and second portions. The first portion is provided on the SiC substrate and the second portion is provided on the first portion. The second portion has a higher carrier concentration than the first portion. Related methods of fabricating BJTs are also provided herein.
    Type: Application
    Filed: September 16, 2005
    Publication date: October 11, 2007
    Inventors: Anant Agarwal, Sumithra Krishnaswami, Sei-Hyung Ryu, Edward Hurt
  • Patent number: 7247513
    Abstract: A method of forming a layer of silicon carbide wherein silicon clusters are dissociated in a gas phase. Silicon clusters may be dissociated by a silicon-etching gas such as a group VII-containing component. A semiconductor device is also disclosed having a layer formed by the methods of the invention.
    Type: Grant
    Filed: May 8, 2003
    Date of Patent: July 24, 2007
    Assignee: Caracal, Inc.
    Inventor: Olof Claes Erik Kordina
  • Patent number: 7118973
    Abstract: The vertical diffusion of dopants from the gate and the bulk material into the channel region, and the lateral diffusion of dopants from the source and drain regions into the channel region resulting from thermal cycling during the fabrication of a MOS transistor is minimized by forming the source and drain regions in a layer of composite material that includes silicon, germanium, and carbon.
    Type: Grant
    Filed: June 16, 2004
    Date of Patent: October 10, 2006
    Assignee: National Semiconductor Corporation
    Inventor: Abdalla Aly Naem