Schottky Diode (epo) Patents (Class 257/E21.368)
  • Patent number: 8927402
    Abstract: A termination structure for a nitride-based Schottky diode includes a guard ring formed by an epitaxially grown P-type nitride-based compound semiconductor layer and dielectric field plates formed on the guard ring. The termination structure is formed at the edge of the anode electrode of the Schottky diode and has the effect of reducing electric field crowding at the anode electrode edge, especially when the Schottky diode is reverse biased. In one embodiment, the P-type epitaxial layer includes a step recess to further enhance the field spreading effect of the termination structure.
    Type: Grant
    Filed: May 28, 2014
    Date of Patent: January 6, 2015
    Assignee: Alpha and Omega Semiconductor Incorporated
    Inventors: TingGang Zhu, Anup Bhalla, Madhur Bobde
  • Patent number: 8860169
    Abstract: The present invention aims to enhance the reliability of a semiconductor device equipped with a Schottky barrier diode within the same chip, and its manufacturing technology. The semiconductor device includes an n-type n-well region formed over a p-type semiconductor substrate, an n-type cathode region formed in part thereof and higher in impurity concentration than the n-well region, a p-type guard ring region formed so as to surround the n-type cathode region, an anode conductor film formed so as to integrally cover the n-type cathode region and the p-type guard ring region and to be electrically coupled thereto, n-type cathode conduction regions formed outside the p-type guard ring region with each separation portion left therebetween, and a cathode conductor film formed so as to cover the n-type cathode conduction regions and to be electrically coupled thereto. The anode conductor film and the n-type cathode region are Schottky-coupled to each other.
    Type: Grant
    Filed: November 6, 2013
    Date of Patent: October 14, 2014
    Assignee: Renesas Electronics Corporation
    Inventors: Kunihiko Kato, Hideki Yasuoka, Masatoshi Taya, Masami Koketsu
  • Patent number: 8772144
    Abstract: A vertical conduction nitride-based Schottky diode is formed using an insulating substrate which was lifted off after the diode device is encapsulated on the front side with a wafer level molding compound. The wafer level molding compound provides structural support on the front side of the diode device to allow the insulating substrate to be lifted off so that a conductive layer can be formed on the backside of the diode device as the cathode electrode. A vertical conduction nitride-based Schottky diode is thus realized. In another embodiment, a protection circuit for a vertical GaN Schottky diode employs a silicon-based vertical PN junction diode connected in parallel to the GaN Schottky diode to divert reverse bias avalanche current.
    Type: Grant
    Filed: November 11, 2011
    Date of Patent: July 8, 2014
    Assignee: Alpha and Omega Semiconductor Incorporated
    Inventors: TingGang Zhu, Anup Bhalla, Ping Huang, Yueh-se Ho
  • Patent number: 8759935
    Abstract: A power semiconductor device includes an active device region disposed in a semiconductor substrate, an edge termination region disposed in the semiconductor substrate between the active device region and a lateral edge of the semiconductor substrate and a trench disposed in the edge termination region which extends from a first surface of the semiconductor substrate toward a second opposing surface of the semiconductor substrate. The trench has an inner sidewall, an outer sidewall and a bottom. The inner sidewall is spaced further from the lateral edge of the semiconductor substrate than the outer sidewall, and an upper portion of the outer sidewall is doped opposite as the inner sidewall and bottom of the trench to increase the blocking voltage capacity. Other structures can be provided which yield a high blocking voltage capacity such as a second trench or a region of chalcogen dopant atoms disposed in the edge termination region.
    Type: Grant
    Filed: June 3, 2011
    Date of Patent: June 24, 2014
    Assignee: Infineon Technologies Austria AG
    Inventor: Gerhard Schmidt
  • Patent number: 8716745
    Abstract: A diode is defined on a die. The diode includes a substrate of P conductivity having an upper surface and a lower surface, the substrate having first and second ends corresponding to first and second edges of the die. An anode contacts the lower surface of the substrate. A layer of N conductivity is provided on the upper surface of the substrate, the layer having an upper surface and a lower surface. A doped region of N conductivity is formed at an upper portion of the layer. A cathode contacts the doped region. A passivation layer is provided on the upper surface of the layer and proximate to the cathode.
    Type: Grant
    Filed: May 11, 2006
    Date of Patent: May 6, 2014
    Assignee: IXYS Corporation
    Inventor: Subhas Chandra Bose Jayappa Veeramma
  • Patent number: 8604583
    Abstract: The present invention aims to enhance the reliability of a semiconductor device equipped with a Schottky barrier diode within the same chip, and its manufacturing technology. The semiconductor device includes an n-type n-well region formed over a p-type semiconductor substrate, an n-type cathode region formed in part thereof and higher in impurity concentration than the n-well region, a p-type guard ring region formed so as to surround the n-type cathode region, an anode conductor film formed so as to integrally cover the n-type cathode region and the p-type guard ring region and to be electrically coupled thereto, n-type cathode conduction regions formed outside the p-type guard ring region with each separation portion left therebetween, and a cathode conductor film formed so as to cover the n-type cathode conduction regions and to be electrically coupled thereto. The anode conductor film and the n-type cathode region are Schottky-coupled to each other.
    Type: Grant
    Filed: April 3, 2012
    Date of Patent: December 10, 2013
    Assignee: Renesas Electronics Corporation
    Inventors: Kunihiko Kato, Hideki Yasuoka, Masatoshi Taya, Masami Koketsu
  • Patent number: 8581359
    Abstract: A Schottky barrier diode includes a GaN freestanding substrate having a front surface, a GaN epitaxial layer deposited on the front surface, and an insulation layer deposited on the GaN epitaxial layer at a front surface and having an opening. Furthermore, the Schottky barrier diode also includes an electrode. The electrode is configured by a Schottky electrode provided in the opening in contact with the GaN epitaxial layer, and a field plate electrode connected to the Schottky electrode and also overlapping the insulation layer. The GaN freestanding substrate has a dislocation density of at most 1×108 cm?2.
    Type: Grant
    Filed: August 22, 2008
    Date of Patent: November 12, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Taku Horii, Tomihito Miyazaki, Makoto Kiyama
  • Patent number: 8492254
    Abstract: A method of manufacturing a semiconductor device is disclosed. The method includes forming a first trench and a second trench in an n-type substrate surface, the first trenches being spaced apart from each other, the second trench surrounding the first trenches, the second trench being wider than the first trench. The method also includes forming a gate oxide film on the inner surfaces of the first and second trenches, and depositing an electrically conductive material to the thickness a half or more as large as the first trench width. The method further includes removing the electrically conductive material using the gate oxide film as a stopper layer, forming an insulator film thicker than the gate oxide film, and polishing the insulator film by CMP for exposing the n-type substrate and the electrically conductive material in the first trench.
    Type: Grant
    Filed: November 10, 2011
    Date of Patent: July 23, 2013
    Assignee: Fuji Electric Co., Ltd.
    Inventor: Tomonori Mizushima
  • Patent number: 8338906
    Abstract: An integrated circuit structure has a metal silicide layer formed on an n-type well region, a p-type guard ring formed on the n-type well region and encircling the metal silicide layer. The outer portion of the metal silicide layer extends to overlap the inner edge of the guard ring, and a Schottky barrier is formed at the junction of the internal portion of the metal silicide layer and the well region. A conductive contact is in contact with the internal portion and the outer portion of the metal silicide layer.
    Type: Grant
    Filed: December 8, 2008
    Date of Patent: December 25, 2012
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Ping-Chun Yeh, Der-Chyang Yeh, Ruey-Hsin Liu, Mingo Liu
  • Publication number: 20120282762
    Abstract: A method for forming a gallium nitride based semiconductor diode includes forming Schottky contacts on the upper surface of mesas formed in a semiconductor body formed on a substrate. Ohmic contacts are formed on the lower surface of the semiconductor body. In one embodiment, an insulating layer is formed over the Schottky and ohmic contacts and vias are formed in the insulating layer to the Schottky and ohmic contacts to form the anode and cathode electrodes. In another embodiment, vias are formed in the insulating layer to the Schottky contacts and vias are formed in the semiconductor body to the ohmic contacts. An anode electrode is formed in electrical contact with the Schottky contacts. A cathode electrode is formed in electrical contact with the ohmic contacts on the backside of the substrate.
    Type: Application
    Filed: July 19, 2012
    Publication date: November 8, 2012
    Applicant: ALPHA & OMEGA SEMICONDUCTOR, INC.
    Inventor: TingGang Zhu
  • Publication number: 20120256288
    Abstract: A Schottky diode and a method for making one. The method includes the following steps: providing a semiconductor base body, preferably in the form of a wafer, having a high dopant concentration and having a first main surface, which forms the first electrical contact surface of the Schottky diode; epitaxially depositing a semiconductor layer having the same conductivity and a lower dopant concentration on that surface of the semiconductor base body which lies opposite the first main surface; arranging a first metal layer on the semiconductor layer with the formation of a Schottky contact between the first metal layer and the semiconductor layer; connecting a planar contact body to the first metal layer by means of a connecting means; forming at least one individual Schottky diode; and arranging a passivation layer in the edge region of the at least one Schottky diode.
    Type: Application
    Filed: March 30, 2012
    Publication date: October 11, 2012
    Applicant: Semikron Elektronik GmbH & Ko. KG
    Inventors: Stefan STAROVECKY, Olga Krempaska, Martin Predmersky
  • Publication number: 20120175724
    Abstract: A Schottky diode with a small footprint and a high-current carrying ability is fabricated by forming an opening that extends into an n-type semiconductor material. The opening is then lined with a metallic material such as platinum. The metallic material is then heated to form a salicide region where the metallic material touches the n-type semiconductor material.
    Type: Application
    Filed: January 6, 2011
    Publication date: July 12, 2012
    Inventors: Sheldon D. Haynie, Ann Gabrys
  • Patent number: 8183103
    Abstract: A method for manufacturing an integrated circuit structure is disclosed. First, a dielectric layer is formed on a substrate, the substrate has a transistor region and a diode region. Next, a contact hole and an opening are formed in the dielectric layer, a size of the opening being larger than that of the contact hole. Next, a first metal layer is formed on the dielectric layer and filled into the contact hole and the opening. Next, a portion of the first metal layer is removed to form a contact plug above the transistor region and form a metal spacer on a sidewall of the opening. Next, an ion implantation process is performed to form a lightly doped region in the substrate at a bottom of the opening. Finally, a contact metal layer is formed on the lightly doped region.
    Type: Grant
    Filed: March 4, 2010
    Date of Patent: May 22, 2012
    Assignee: United Microelectronics Corp.
    Inventor: Yan-Hsiu Liu
  • Patent number: 8169047
    Abstract: The present invention aims to enhance the reliability of a semiconductor device equipped with a Schottky barrier diode within the same chip, and its manufacturing technology. The semiconductor device includes an n-type n-well region formed over a p-type semiconductor substrate, an n-type cathode region formed in part thereof and higher in impurity concentration than the n-well region, a p-type guard ring region formed so as to surround the n-type cathode region, an anode conductor film formed so as to integrally cover the n-type cathode region and the p-type guard ring region and to be electrically coupled thereto, n-type cathode conduction regions formed outside the p-type guard ring region with each separation portion left therebetween, and a cathode conductor film formed so as to cover the n-type cathode conduction regions and to be electrically coupled thereto. The anode conductor film and the n-type cathode region are Schottky-coupled to each other.
    Type: Grant
    Filed: September 5, 2008
    Date of Patent: May 1, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Kunihiko Kato, Hideki Yasuoka, Masatoshi Taya, Masami Koketsu
  • Patent number: 8143655
    Abstract: A fabrication process for a trench Schottky diode with differential oxide thickness within the trenches includes forming a first nitride layer on a substrate surface and subsequently forming a plurality of trenches in the substrate including, possibly, a termination trench. Following a sacrificial oxide layer formation and removal, sidewall and bottom surfaces of the trenches are oxidized. A second nitride layer is then applied to the substrate and etched such that the second nitride layer covers the oxide layer on the trench sidewalls but exposes the oxide layer on the trench bottom surfaces. The trench bottom surfaces are then re-oxidized and the remaining second nitride layer then removed from the sidewalls, resulting in an oxide layer of varying thickness being formed on the sidewall and bottom surfaces of each trench. The trenches are then filled with a P type polysilicon, the first nitride layer removed, and a Schottky barrier metal applied to the substrate surface.
    Type: Grant
    Filed: October 11, 2007
    Date of Patent: March 27, 2012
    Assignee: International Rectifier Corporation
    Inventor: Davide Chiola
  • Patent number: 8030193
    Abstract: To fabricate a Schottky barrier diode in which a decrease in on current due to parasitic resistance is suppressed, variations in on current are suppressed, and an increase in off current is suppressed. The fabricating method includes the steps of forming an island-shape semiconductor film; doping the island-shape semiconductor film with a first impurity element to form a first impurity region; forming an insulating film so as to cover the island-shape semiconductor film; etching the insulating film to form a first opening and a second opening that partly expose the first impurity region; forming a mask over the insulating film so as to cover the first opening and expose the second opening; doping the first impurity region with a second impurity element to form a second impurity region; and forming a first wiring in contact with the first impurity region exposed at the first opening, and forming a second wiring in contact with the second impurity region exposed at the second opening.
    Type: Grant
    Filed: December 13, 2007
    Date of Patent: October 4, 2011
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Atsuo Isobe, Suguru Ozawa
  • Publication number: 20110084353
    Abstract: A trench Schottky rectifier device includes a substrate having a first conductivity type, a plurality of trenches formed in the substrate, and an insulating layer formed on sidewalls of the trenches. The trenches are filled with conductive structure. There is an electrode overlying the conductive structure and the substrate, and thus a Schottky contact forms between the electrode and the substrate. A plurality of embedded doped regions having a second conductivity type are formed in the substrate and located under the trenches. Each doped region and the substrate form a PN junction to pinch off current flowing toward the Schottky contact so as to suppress current leakage.
    Type: Application
    Filed: October 12, 2010
    Publication date: April 14, 2011
    Applicant: PFC DEVICE CORPORATION
    Inventors: Kou-Liang CHAO, Mei-Ling Chen, Tse-Chuan Su, Hung-Hsin Kuo
  • Patent number: 7915703
    Abstract: Fabrication of a Schottky diodes may include providing a Schottky contact layer containing a low barrier metal layer with spaced apart high barrier metal islands therein on a first surface of a substrate. A diode contact is formed on a second surface of the substrate that is opposite to the first surface. Formation of the Schottky contact layer may include providing a liquid mixture of a high barrier metal and a low barrier metal on the first surface of the substrate. Temperature and/or relative concentrations of the high and low barrier metals in the liquid mixture may be controlled to cause regions of the high barrier metal to solidify within the liquid mixture and agglomerate to form the spaced apart high barrier metal islands while inhibiting solidification of the low barrier metal. The temperature and relative concentrations may then be controlled to cause the low barrier metal to solidify and form the low barrier metal layer containing the high barrier metal islands.
    Type: Grant
    Filed: May 13, 2009
    Date of Patent: March 29, 2011
    Assignee: Cree, Inc.
    Inventors: Jason Patrick Henning, Allan Ward
  • Patent number: 7902055
    Abstract: An embodiment of the invention is a Schottky diode 22 having a semiconductor substrate 3, a first metal 24, a barrier layer 26, and second metal 28. Another embodiment of the invention is a method of manufacturing a Schottky diode 22 that includes providing a semiconductor substrate 3, forming a barrier layer 26 over the semiconductor substrate 3, forming a first metal layer 23 over the semiconductor substrate 3, annealing the semiconductor substrate 3 to form areas 24 of reacted first metal and areas 23 of un-reacted first metal, and removing selected areas 23 of the un-reacted first metal. The method further includes forming a second metal layer 30 over the semiconductor substrate 3 and annealing the semiconductor substrate 3 to form areas 28 of reacted second metal and areas 30 of un-reacted second metal.
    Type: Grant
    Filed: March 30, 2005
    Date of Patent: March 8, 2011
    Assignee: Texas Instruments Incoprorated
    Inventors: Richard B. Irwin, Tony T. Phan, Hong-Ryong Kim, Ming-Yeh Chuang, Jennifer S. Dumin, Patrick J. Jones, Fredric D. Bailey
  • Patent number: 7863172
    Abstract: A gallium nitride based semiconductor Schottky diode fabricated from a n+ doped GaN layer having a thickness between one and six microns disposed on a sapphire substrate; an n? doped GaN layer having a thickness greater than one micron disposed on said n+ GaN layer patterned into a plurality of elongated fingers and a metal layer disposed on the n? doped GaN layer and forming a Schottky junction therewith. The layer thicknesses and the length and width of the elongated fingers are optimized to achieve a device with breakdown voltage of greater than 500 volts, current capacity in excess of one ampere, and a forward voltage of less than three volts.
    Type: Grant
    Filed: October 10, 2008
    Date of Patent: January 4, 2011
    Assignee: Power Integrations, Inc.
    Inventors: TingGang Zhu, Bryan S. Shelton, Marek K. Pabisz, Mark Gottfried, Linlin Liu, Milan Pophristic, Michael Murphy, Richard A. Stall
  • Patent number: 7820473
    Abstract: A Schottky diode capable of sustaining a voltage of greater than about 250 volts and a method for its manufacture. An epitaxial layer of N-type conductivity is disposed on a semiconductor substrate of N-type conductivity. A guard ring of P-type conductivity extends into the epitaxial layer from its surface. A stacked structure is formed on a portion of the guard ring and a portion of the epitaxial layer. The stacked structure includes a layer of semi-insulating semiconductor material disposed on a layer of dielectric material. A first metal layer is formed on the portion of the epitaxial layer adjacent a first side of the stacked structure and on a first portion of the stacked structure. A second metal layer is formed on the portion of the epitaxial layer adjacent a second side of the stacked structure and on a second portion of the stacked structure.
    Type: Grant
    Filed: March 21, 2005
    Date of Patent: October 26, 2010
    Assignee: Semiconductor Components Industries, LLC
    Inventors: Linghui Chen, Blanca Estela Kruse, Mark Duskin, John D. Moran
  • Patent number: 7781859
    Abstract: An integrated circuit structure includes a semiconductor substrate; a well region of a first conductivity type over the semiconductor substrate; a metal-containing layer on the well region, wherein the metal-containing layer and the well region form a Schottky barrier; an isolation region encircling the metal-containing layer; and a deep-well region of a second conductivity type opposite the first conductivity type under the metal-containing layer. The deep-well region has at least a portion vertically overlapping a portion of the metal-containing layer. The deep-well region is vertically spaced apart from the isolation region and the metal-containing layer by the well region.
    Type: Grant
    Filed: March 24, 2008
    Date of Patent: August 24, 2010
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Puo-Yu Chiang, Tsai Chun Lin, Chih-Wen (Albert) Yao, David Ho
  • Patent number: 7777292
    Abstract: A semiconductor device includes a semiconductor substrate of a first conductivity type having a top surface and a bottom surface, a semiconductor layer of a first conductivity type formed on the top surface of the semiconductor substrate, and having an active region and an edge termination region surrounding the active region, a first semiconductor region of a second conductivity type formed in the edge termination region adjacent to an edge of the active region, a second semiconductor region of a second conductivity type buried in the edge termination region in a sheet shape or a mesh shape substantially in parallel with a surface of the semiconductor layer, a first electrode formed on the active region of the semiconductor layer and a part of the first semiconductor region, and a second electrode formed on the bottom surface of the semiconductor substrate.
    Type: Grant
    Filed: June 25, 2007
    Date of Patent: August 17, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Chiharu Ota, Johji Nishio, Tetsuo Hatakeyama, Takashi Shinohe
  • Patent number: 7772599
    Abstract: A gallium-nitride-based semiconductor stacked structure includes a low-temperature-deposited buffer layer and an active layer. The low-temperature-deposited buffer layer is composed of a Group III nitride material that has been grown at low temperature and includes a single-crystal layer in an as-grown state, the single-crystal layer being present in the vicinity of a junction area that is in contact with a (0001) (c) plane of a sapphire substrate. The active layer is composed of a gallium-nitride (GaN)-based semiconductor layer that is provided on the low-temperature-deposited buffer layer. The single-crystal layer is composed of a hexagonal AlXGaYN (0.5<X?1, X+Y=1) crystal that contains aluminum in a predominant amount with respect to gallium such that a [2.?1.?1.0.] direction of the AlXGaYN crystal orients along with a [2.?1.?1.0.] direction of the (0001) bottom plane of the sapphire substrate.
    Type: Grant
    Filed: May 25, 2005
    Date of Patent: August 10, 2010
    Assignee: Showa Denko K.K.
    Inventor: Takashi Udagawa
  • Patent number: 7651905
    Abstract: An apparatus and method for the reduction of gate leakage in deep sub-micron metal oxide semiconductor (MOS) transistors, especially useful for those used in a cross coupled static random access memory (SRAM) cell, is disclosed. In accordance with the invention, the active element of the SRAM cell is used to reduce the voltage on the gate of its transistor without impacting the switching speed of the circuit. Because the load on the output of the inverter is fixed, a reduction in the gate current is optimized to minimize the impact on the switching waveform of the memory cell. An active element formed by two materials with different Fermi potentials is used as a rectifying junction or diode. The rectifying junction also has a large parallel leakage path, which allows a finite current flow when a signal of opposite polarity is applied across this device.
    Type: Grant
    Filed: April 19, 2005
    Date of Patent: January 26, 2010
    Assignee: Semi Solutions, LLC
    Inventor: Ashok Kumar Kapoor
  • Patent number: 7618884
    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: April 21, 2008
    Date of Patent: November 17, 2009
    Assignee: Fairchild Semiconductor Corporation
    Inventors: William F. Seng, Richard L. Woodin, Carl Anthony Witt
  • Patent number: 7588958
    Abstract: To reduce a reverse leakage current in a Schottky barrier diode with achieving a lower forward voltage Vf and a smaller capacitance than in the related art, a Schottky barrier diode includes a semiconductor layer of a first conductivity type, a first electrode which is a metal layer forming a Schottky contact with a main surface of the semiconductor layer, a second electrode forming an ohmic contact with an opposite main surface of the semiconductor layer, a buried layer of a second conductivity type formed within the semiconductor layer so as not to be in contact with the first electrode, where the second conductivity type has a different charge carrier from the first conductivity type, and a guard ring of the second conductivity type formed within the semiconductor layer so as to be in contact with the first electrode and also to surround the buried layer without contacting with the buried layer.
    Type: Grant
    Filed: April 18, 2006
    Date of Patent: September 15, 2009
    Assignee: Panasonic Corporation
    Inventors: Yuji Tanaka, Naotoshi Kashima
  • Patent number: 7521329
    Abstract: A semiconductor light emitting diode having a textured structure and a method of manufacturing the semiconductor light emitting diode are provided. The method includes forming a first semiconductor layer on a substrate; forming a textured structured first semiconductor layer by penetrating a material of a material layer into the first semiconductor layer after the material layer is formed on the first semiconductor layer and is annealed; and forming a second semiconductor layer on the first semiconductor layer.
    Type: Grant
    Filed: December 30, 2005
    Date of Patent: April 21, 2009
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Joon-seop Kwak, Jeong-wook Lee
  • Patent number: 7391056
    Abstract: Electron-hole production at a Schottky barrier has recently been observed experimentally as a result of chemical processes. This conversion of chemical energy to electronic energy may serve as a basic link between chemistry and electronics and offers the potential for generation of unique electronic signatures for chemical reactions and the creation of a new class of solid state chemical sensors. Detection of the following chemical species was established: hydrogen, deuterium, carbon monoxide, molecular oxygen. The detector (1b) consists of a Schottky diode between an Si layer and an ultrathin metal layer with zero force electrical contacts.
    Type: Grant
    Filed: September 28, 2005
    Date of Patent: June 24, 2008
    Assignee: Adrena, Inc.
    Inventors: Eric W. McFarland, Henry W. Weinberg, Hermann Nienhaus, Howard S. Bergh, Brian Gergen, Arunava Mujumdar
  • Patent number: 7323402
    Abstract: A fabrication process for a trench Schottky diode with differential oxide thickness within the trenches includes forming a first nitride layer on a substrate surface and subsequently forming a plurality of trenches in the substrate including, possibly, a termination trench. Following a sacrificial oxide layer formation and removal, sidewall and bottom surfaces of the trenches are oxidized. A second nitride layer is then applied to the substrate and etched such that the second nitride layer covers the oxide layer on the trench sidewalls but exposes the oxide layer on the trench bottom surfaces. The trench bottom surfaces are then re-oxidized and the remaining second nitride layer then removed from the sidewalls, resulting in an oxide layer of varying thickness being formed on the sidewall and bottom surfaces of each trench. The trenches are then filled with a P type polysilicon, the first nitride layer removed, and a Schottky barrier metal applied to the substrate surface.
    Type: Grant
    Filed: January 14, 2005
    Date of Patent: January 29, 2008
    Assignee: International Rectifier Corporation
    Inventor: Davide Chiola
  • Patent number: 7314770
    Abstract: A method of making a light emitting device is disclosed. The method includes the steps of providing a light emitting diode and forming an encapsulant in contact with the light emitting diode; wherein forming the encapsulant includes contacting the light emitting diode with a photopolymerizable composition consisting of a silicon-containing resin and a metal-containing catalyst, wherein the silicon-containing resin consists of silicon-bonded hydrogen and aliphatic unsaturation, and applying actinic radiation having a wavelength of 700 nm or less to initiate hydrosilylation within the silicon-containing resin.
    Type: Grant
    Filed: October 17, 2005
    Date of Patent: January 1, 2008
    Assignee: 3M Innovative Properties Company
    Inventors: Larry D. Boardman, D. Scott Thompson, Catherine A. Leatherdale, Andrew J. Ouderkirk
  • Patent number: 7282429
    Abstract: Embodiments of the invention provide a method of manufacturing a Schottky diode device. In one embodiment, the method includes: (a) providing a substrate; (b) sequentially forming a gate oxide layer and a polysilicon layer on the substrate; (c) partially oxidizing the polysilicon layer to form a poly oxide layer on the polysilicon layer; (d) forming and defining a photoresist layer on the poly oxide layer for exposing parts of the poly oxide layer; (e) etching the poly oxide layer, the polysilicon layer and the gate oxide layer via the photoresist layer for forming a poly oxide structure, a polysilicon structure and a gate oxide structure; and (f) removing the photoresist layer. The present invention introduces a poly oxide layer instead of the CVD oxide for preventing the photoresist lifting issue.
    Type: Grant
    Filed: August 19, 2005
    Date of Patent: October 16, 2007
    Assignee: Mosel Vitelic, Inc.
    Inventors: Shih-Chi Lai, Pei-Feng Sun, Yi Fu Chung, Jen Chieh Chang
  • Patent number: 7268005
    Abstract: An apparatus for stacking photonic devices is disclosed. The apparatus can include a base, first and second spaced apart rail portions disposed on the base, and a vacuum guide disposed on the base between the rail portions for forming a vacuum gradient that pulls a plurality of photonic devices and spacer bars together into a stack. Optionally, spaced apart photonic device supports can be placed on the base between the rail portions to lift the photonic devices off of the surface of the base. The apparatus can also include a clamping system to hold the stack in place so that a vapor deposition process can be used to apply coatings to the photonic devices. In one exemplary embodiment, the photonic devices can be laser bars.
    Type: Grant
    Filed: October 27, 2003
    Date of Patent: September 11, 2007
    Assignee: Finisar Corporation
    Inventors: John Chen, Chun Lei, Robert Shih