With Electric Field Controlling Semiconductor Layer Having A Low Enough Doping Level In Relationship To Its Thickness To Be Fully Depleted Prior To Avalanche Breakdown (e.g., Resurf Devices) Patents (Class 257/493)
  • Patent number: 8288839
    Abstract: A vertical transient voltage suppressing (TVS) device includes a semiconductor substrate of a first conductivity type where the substrate is heavily doped, an epitaxial layer of the first conductivity type formed on the substrate where the epitaxial layer has a first thickness, and a base region of a second conductivity type formed in the epitaxial layer where the base region is positioned in a middle region of the epitaxial layer. The base region and the epitaxial layer provide a substantially symmetrical vertical doping profile on both sides of the base region. In one embodiment, the base region is formed by high energy implantation. In another embodiment, the base region is formed as a buried layer. The doping concentrations of the epitaxial layer and the base region are selected to configure the TVS device as a punchthrough diode based TVS or an avalanche mode TVS.
    Type: Grant
    Filed: April 30, 2009
    Date of Patent: October 16, 2012
    Assignee: Alpha & Omega Semiconductor, Inc.
    Inventors: Lingpeng Guan, Madhur Bobde, Anup Bhalla
  • Patent number: 8274129
    Abstract: A method includes forming a transistor device on a first side of a semiconductor-on-insulator structure. The semiconductor-on-insulator structure includes a substrate, a dielectric layer, and a buried layer between the substrate and the dielectric layer. The method also includes forming a conductive plug through the semiconductor-on-insulator structure. The conductive plug is in electrical connection with the transistor device. The method further includes forming a field plate on a second side of the semiconductor-on-insulator structure, where the field plate is in electrical connection with the conductive plug. The transistor device could have a breakdown voltage of at least 600V, and the field plate could extend along at least 40% of a length of the transistor device.
    Type: Grant
    Filed: October 23, 2009
    Date of Patent: September 25, 2012
    Assignee: National Semiconductor Corporation
    Inventors: William French, Peter Smeys, Peter J. Hopper, Peter Johnson
  • Patent number: 8269270
    Abstract: A vertical semiconductor component having a semiconductor body, which has an inner region and an edge region that is arranged between the inner region and an edge of the semiconductor body. At least one semiconductor junction between a first semiconductor zone of a first conduction type, said first semiconductor zone being arranged in the region of a first side of the semiconductor body in the inner region, and a second semiconductor zone of the second conduction type, said second semiconductor zone adjoining the first semiconductor zone in the vertical direction.
    Type: Grant
    Filed: December 20, 2004
    Date of Patent: September 18, 2012
    Assignee: Infineon Technologies AG
    Inventors: Anton Mauder, Hans-Joachim Schulze
  • Patent number: 8242572
    Abstract: A semiconductor apparatus includes, below a high-voltage wiring, a p? diffusion layer in contact with an n drain buffer layer and a p+ diffusion layer in contact with a p? diffusion layer for reducing the electric field strength in an insulator film, which the high-voltage wiring crosses over. Reducing electric field strength in the insulator film prevents lowering of breakdown voltage of a high-voltage NMOSFET, break down of an interlayer insulator film, and impairment of isolation breakdown voltage of a device isolation trench. The semiconductor apparatus according to the invention facilitates bridging a high-voltage wiring from a high-voltage NMOSFET and such a level-shifting device to a high-voltage floating region crossing over a device isolation trench without impairing the breakdown voltage of the high-voltage NMOSFET, without breaking down the interlayer insulator film and without impairing the isolation breakdown voltage of the device isolation trench.
    Type: Grant
    Filed: November 2, 2010
    Date of Patent: August 14, 2012
    Assignee: Fuji Electric Co., Ltd.
    Inventor: Masaharu Yamaji
  • Patent number: 8227868
    Abstract: A semiconductor device according to the present invention includes a semiconductor substrate of a first conductivity type having a top surface and a rear surface, a semiconductor layer of a second conductivity type formed on the top surface of the semiconductor substrate, having a top surface and a rear surface, and having the rear surface in contact with the top surface of the semiconductor substrate, a body region of the first conductivity type formed in a top layer portion of the semiconductor layer, a first impurity region of the second conductivity type formed in a top layer portion of the semiconductor layer and spaced apart from the body region, a second impurity region of the second conductivity type formed in a top layer portion of the body region and spaced apart from a peripheral edge of the body region, a gate electrode formed on the semiconductor layer and opposed to a portion between the peripheral edge of the body region and a peripheral edge of the second impurity region, a field insulating fi
    Type: Grant
    Filed: January 31, 2011
    Date of Patent: July 24, 2012
    Assignee: Rohm Co., Ltd.
    Inventor: Daisuke Ichikawa
  • Patent number: 8212329
    Abstract: A short channel Lateral MOSFET (LMOS) and method are disclosed with interpenetrating drain-body protrusions (IDBP) for reducing channel-on resistance while maintaining high punch-through voltage. The LMOS includes lower device bulk layer; upper source and upper drain region both located atop lower device bulk layer; both upper source and upper drain region are in contact with an intervening upper body region atop lower device bulk layer; both upper drain and upper body region are shaped to form a drain-body interface; the drain-body interface has an IDBP structure with a surface drain protrusion lying atop a buried body protrusion while revealing a top body surface area of the upper body region; gate oxide-gate electrode bi-layer disposed atop the upper body region forming an LMOS with a short channel length defined by the horizontal length of the top body surface area delineated between the upper source region and the upper drain region.
    Type: Grant
    Filed: November 6, 2010
    Date of Patent: July 3, 2012
    Assignee: Alpha and Omega Semiconductor Inc.
    Inventors: Shekar Mallikarjunaswamy, Amit Paul
  • Publication number: 20120119319
    Abstract: A semiconductor device includes a first semiconductor region and a second semiconductor region provided on a main surface of a substrate, being apart from each other and having first conductivity; a third semiconductor region provided between the first semiconductor region and the second semiconductor region and having second conductivity opposite to the first conductivity; a fourth semiconductor region provided on a main surface of the substrate, connected to the third semiconductor region, manufactured together with the third semiconductor region in the same manufacturing process, and having the conductivity same as that of the third semiconductor region; and trenches made on the main surface of the fourth semiconductor region and having a depth smaller than a junction depth of the fourth semiconductor region.
    Type: Application
    Filed: January 20, 2012
    Publication date: May 17, 2012
    Applicant: Sanken Electric Co., Ltd.
    Inventor: Hironori AOKI
  • Patent number: 8148758
    Abstract: A high-voltage field-effect device contains an extended drain or “drift” region including an embedded stack of JFET regions separated by intervening layers of the drift region. Each of the JFET regions is filled with material of an opposite conductivity type to that of the drift region, and the floor and ceiling of each JFET region is lined with an oxide layer. When the device is blocking a voltage in the off condition, the semiconductor material inside the JFET regions and in the drift region that separates the JFET regions is depleted. This improves the voltage-blocking ability of the device while conserving chip area. The oxide layer prevents dopant from the JFET regions from diffusing into the drift region.
    Type: Grant
    Filed: December 16, 2010
    Date of Patent: April 3, 2012
    Assignee: Alpha and Omega Semiconductor Inc.
    Inventor: Hamza Yilmaz
  • Patent number: 8143691
    Abstract: To provide a semiconductor device and a method of making the same, the device being capable of preventing decrease in the withstanding voltage along the direction perpendicular to the source-drain direction and thereby improving the resistance to an overvoltage (overcurrent), the device includes: a p-type semiconductor substrate 201; an n-type diffusion region 202; a p-type body region 206, a p-type buried diffusion region 204, and an n-type drift region 207 within the n-type diffusion region 202; an n-type source region 208 and a p-type body contact region 209 within the p-type body region 206; an n-type drain region 210 within the n-type drift region 207; a gate insulating film above the p-type body region 206; and a gate electrode 211 above the gate insulating film, where the region 204 extends away from the region 206 farther than the farther edge of the gate electrode 211 is along a cross section perpendicular to the source-drain direction.
    Type: Grant
    Filed: September 10, 2009
    Date of Patent: March 27, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Hisao Ichijo
  • Patent number: 8138570
    Abstract: An isolation structure for a semiconductor device comprises a floor isolation region, a dielectric filled trench above the floor isolation region and a sidewall isolation region extending downward from the bottom of the trench to the floor isolation region. This structure provides a relatively deep isolated pocket in a semiconductor substrate while limiting the depth of the trench that must be etched in the substrate. An isolated junction field-effect transistor is formed in the isolated pocket.
    Type: Grant
    Filed: December 17, 2007
    Date of Patent: March 20, 2012
    Assignees: Advanced Analogic Technologies, Inc., Advanced Analogic Technologies (Hong Kong) Limited
    Inventors: Richard K. Williams, Donald Ray Disney, Wai Tien Chan
  • Publication number: 20120061758
    Abstract: A semiconductor device and a related fabrication process are presented here. The device includes a support substrate, a buried oxide layer overlying the support substrate, a first semiconductor region located above the buried oxide layer and having a first conductivity type. The device also includes second, third, fourth, and fifth semiconductor regions. The second semiconductor region is located above the first semiconductor region, and it has a second conductivity type. The third semiconductor region is located above the second semiconductor region, and it has the first conductivity type. The fourth semiconductor region is located above the third semiconductor region, and it has the second conductivity type. The fifth semiconductor region extends through the fourth semiconductor region and the third semiconductor region to the second semiconductor region, and it has the second conductivity type.
    Type: Application
    Filed: September 15, 2010
    Publication date: March 15, 2012
    Applicant: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Tahir A. Khan, Bernhard H. Grote, Vishnu K. Khemka, Ronghua Zhu
  • Patent number: 8110889
    Abstract: In one embodiment a method for fabricating a compound nitride semiconductor device comprising positioning one or more substrates on a susceptor in a processing region of a metal organic chemical vapor deposition (MOCVD) chamber comprising a showerhead, depositing a gallium nitride layer over the substrate with a thermal chemical-vapor-deposition process within the MOCVD chamber by flowing a first gallium containing precursor and a first nitrogen containing precursor through the showerhead into the MOCVD chamber, removing the one or more substrates from the MOCVD chamber without exposing the one or more substrates to atmosphere, flowing a chlorine gas into the processing chamber to remove contaminants from the showerhead, transferring the one or more substrates into the MOCVD chamber after removing contaminants from the showerhead, and depositing an InGaN layer over the GaN layer with a thermal chemical-vapor-deposition process within the MOCVD chamber is provided.
    Type: Grant
    Filed: March 24, 2010
    Date of Patent: February 7, 2012
    Assignee: Applied Materials, Inc.
    Inventor: Olga Kryliouk
  • Patent number: 8106454
    Abstract: A vertical power semiconductor device includes a first semiconductor layer of a first conductivity type formed in both a cell section and a termination section, the termination section surrounding the cell section, a second semiconductor layer of a second conductivity type formed on the first semiconductor layer in the cell section, a third semiconductor layer of the first conductivity type formed in part on the second semiconductor layer, and a guard ring layer of the second conductivity type formed on the first semiconductor layer in the termination section. Net impurity concentration in the guard ring layer is generally sloped so as to be relatively high on its lower side and relatively low on its upper side. Alternatively, the net impurity concentration in the guard ring layer is constant.
    Type: Grant
    Filed: November 6, 2008
    Date of Patent: January 31, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Miwako Akiyama, Yusuke Kawaguchi, Yoshihiro Yamaguchi
  • Publication number: 20110309464
    Abstract: A semiconductor device includes a semiconductor substrate and an electric field terminal part. The semiconductor substrate includes a substrate, a drift layer disposed on a surface of the substrate, and a base layer disposed on a surface of the drift layer. The semiconductor substrate is divided into a cell region in which a semiconductor element is disposed and a peripheral region that surrounds the cell region. The base region has a bottom face located on a same plane throughout the cell region and the peripheral region and provides an electric field relaxing layer located in the peripheral region. The electric field terminal part surrounds the cell region and a portion of the electric field relaxing layer and penetrates the electric field relaxing layer from a surface of the electric field relaxing layer to the drift layer.
    Type: Application
    Filed: June 20, 2011
    Publication date: December 22, 2011
    Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, DENSO CORPORATION
    Inventors: Kensaku YAMAMOTO, Naohiro Suzuki, Hidefumi Takaya, Masahiro Sugimoto, Jun Morimoto, Narumasa Soejima, Tsuyoshi Ishikawa, Yukihiko Watanabe
  • Patent number: 8080858
    Abstract: A Semiconductor component having a space saving edge structure is disclosed. One embodiment provides a first side, a second side, an inner region, an edge region adjoining the inner region in a lateral direction of the semiconductor body, and a first semiconductor layer extending across the inner region and the edge region and having a basic doping of a first conductivity type. At least one active component zone of a second conductivity type, which is complementary to the first conductivity type, is disposed in the inner region in the first semiconductor layer. An edge structure is disposed in the edge region and includes at least one trench extending from the first side into the semiconductor body. An edge electrode is disposed in the trench, a dielectric layer is disposed in the trench between the edge electrode and the semiconductor body, a first edge zone of the second conductivity type adjoin the trench and are at least partially disposed below the trench.
    Type: Grant
    Filed: August 3, 2007
    Date of Patent: December 20, 2011
    Assignee: Infineon Technologies Austria AG
    Inventors: Franz Hirler, Ralf Siemieniec, Christian Geissler
  • Publication number: 20110291223
    Abstract: A semiconductor device includes a semiconductor substrate having a diode active region and an edge termination region adjacent to each other, a first region of a first conductivity type in the diode active region, a second region of a second conductivity type, a third region of the first conductivity type in the edge termination region, and a fourth region of the second conductivity type. The first region and the third region share a drift region of the first conductivity type. The first region and the third region share a fifth region of the first conductivity type. The drift region in the third region is greater in number of crystal defects per unit volume than the drift region in the first region in order that the drift region in the third region is shorter in carrier lifetime than the drift region in the first region.
    Type: Application
    Filed: April 25, 2011
    Publication date: December 1, 2011
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventor: Katsumi NAKAMURA
  • Patent number: 8049255
    Abstract: A semiconductor device includes an insulating substrate and a TFT element disposed on the substrate. The TFT element includes a gate electrode, a gate insulating film, a semiconductor layer, and a source electrode and a drain electrode arranged in that order on the insulating substrate. The semiconductor layer includes an active layer composed of polycrystalline semiconductor and a contact layer segment interposed between the active layer and the source electrode and another contact layer segment interposed between the active layer and the drain electrode. The source and drain electrodes each have a first face facing the opposite face of the active layer from the interface with the gate insulating layer and a second face facing an etched side face of the active layer. Each contact layer segment is disposed between the active layer and each of the first and second faces of the source or drain electrode.
    Type: Grant
    Filed: June 5, 2008
    Date of Patent: November 1, 2011
    Assignee: Hitachi Displays, Ltd.
    Inventors: Takeshi Sakai, Toshio Miyazawa, Takuo Kaitoh, Hidekazu Miyake
  • Publication number: 20110233714
    Abstract: Aspects of the invention are related to a semiconductor device including a first conductivity type n-type drift layer, a second conductivity type VLD region which is formed on a chip inner circumferential side of a termination structure region provided on one principal surface of the n-type drift layer and which is higher in concentration than the n-type drift layer, and a second conductivity type first clip layer which is formed on a chip outer circumferential side of the VLD region so as to be separated from the VLD region and which is higher in concentration than the n-type drift layer. The invention can also include a first conductivity type channel stopper layer which is formed on a chip outer circumferential side of the first clip layer so as to be separated from the first clip layer and which is higher in concentration than the n-type drift layer.
    Type: Application
    Filed: March 23, 2011
    Publication date: September 29, 2011
    Applicant: FUJI ELECTRIC SYSTEMS CO. LTD.
    Inventor: Hong-fei LU
  • Publication number: 20110220914
    Abstract: A method of manufacturing a power semiconductor device according to the present invention includes the steps of: (a) forming a silicon nitride film on a semiconductor substrate; (b) after the step (a), forming a ring-shaped trench along a peripheral portion of the semiconductor substrate 6; (c) forming a first silicon oxide film on an inner surface of the trench; (d) after the step (c), forming a second silicon oxide film on an entire surface of the semiconductor substrate to bury the trench; (e) planarizing the second silicon oxide film by using the silicon nitride film as a stopper; and (f) forming a third silicon oxide film in a region in which the silicon nitride film is removed.
    Type: Application
    Filed: December 7, 2010
    Publication date: September 15, 2011
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Ryoichi Fujii, Shigeto Honda, Atsushi Narazaki, Kaoru Motonami
  • Publication number: 20110198693
    Abstract: Provided is a III nitride semiconductor electronic device having a structure capable of reducing leakage current. A laminate 11 includes a substrate 13 and a III nitride semiconductor epitaxial film 15. The substrate 13 is made of a III nitride semiconductor having a carrier concentration of more than 1×1018 cm?3. The epitaxial structure 15 includes a III nitride semiconductor epitaxial film 17. A first face 13a of the substrate 13 is inclined at an angle ? of more than 5 degrees with respect to an axis Cx extending in a direction of the c-axis. A normal vector VN and a c-axis vector VC make the angle ?. The III nitride semiconductor epitaxial film 17 includes first, second and third regions 17a, 17b and 17c arranged in order in a direction of a normal to the first face 13a. A dislocation density of the third region 17c is smaller than that of the first region 17a. A dislocation density of the second region 17b is smaller than that of the substrate 13.
    Type: Application
    Filed: October 20, 2009
    Publication date: August 18, 2011
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Hiromu Shiomi, Kazuhide Sumiyoshu, Yu Saitoh, Makoto Kiyama
  • Patent number: 7999312
    Abstract: A semiconductor 100 has a P? body region and an N? drift region in the order from an upper surface side thereof. A gate trench and a terminal trench passing through the P? body region are formed. The respective trenches are surrounded with P diffusion regions at the bottom thereof. The gate trench builds a gate electrode therein. A P?? diffusion region, which is in contact with the end portion in a lengthwise direction of the gate trench and is lower in concentration than the P? body region and the P diffusion region, is formed. The P?? diffusion region is depleted prior to the P diffusion region when the gate voltage is off. The P?? diffusion region serves as a hole supply path to the P diffusion region when the gate voltage is on.
    Type: Grant
    Filed: January 26, 2007
    Date of Patent: August 16, 2011
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Hidefumi Takaya, Kimimori Hamada, Kyosuke Miyagi
  • Patent number: 7999317
    Abstract: A p-type body region and an n-type buffer region are formed on an n? drift region. An n++ emitter region and a p++ contact region are formed on the p-type body region in contact with each other. A p++ collector region is formed on the n-type buffer region. An insulating film is formed on the n? drift region, and a gate insulating film is formed on the n++ emitter region, the p-type body region, and the n drift region. A gate electrode is formed on the insulating film and the gate insulating film. A p+ low-resistivity region is formed in the p-type body region and surrounding the interface between the n++ emitter region and between the p-type body region and the p++ contact region. The p-type body region has two local maxima of an impurity concentration profile at the interface between the body region and the gate insulating film.
    Type: Grant
    Filed: January 9, 2009
    Date of Patent: August 16, 2011
    Assignee: Fuji Electric Systems Co., Ltd.
    Inventors: Hong-Fei Lu, Mizushima Tomonori
  • Patent number: 7989910
    Abstract: A semiconductor device includes an n+ type semiconductor substrate 1 and a super junction region that has, on the top of the substrate 1, an n and p type pillar regions 2 and 3 provided alternately. The device also includes, in the top surface of the super junction region, a p type base region 4 and an n type source layer 5. The device also includes a gate electrode 7 on the region 4 and layer 5 via a gate-insulating film 6, a drain electrode 9 on the bottom of the substrate 1, and a source electrode 8 on the top of the substrate 1. In the top surface of the super junction region in the terminal region, a RESURF region 10 is formed. The RESURF region has a comb-like planar shape with repeatedly-formed teeth having tips facing the end portion of the terminal region.
    Type: Grant
    Filed: October 16, 2008
    Date of Patent: August 2, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Wataru Saito, Syotaro Ono, Masaru Izumisawa, Yasuto Sumi, Hiroshi Ohta, Wataru Sekine, Nana Hatano
  • Patent number: 7973382
    Abstract: A gate electrode 20 and first field plates 22a to 22d and 23 are provided on a field oxide film 19. The gate electrode 20 and first field plates 22a to 22d and 23 are covered with an insulating film 24. A high-voltage wiring conductor 28 is provided on the insulating film 24. A shielding electrode 29 is provided between the first field plate 22a positioned closest to a source side and the high-voltage wiring conductor 28.
    Type: Grant
    Filed: July 24, 2007
    Date of Patent: July 5, 2011
    Assignee: Mitsubishi Electric Corporation
    Inventor: Tetsuo Takahashi
  • Publication number: 20110084354
    Abstract: In a semiconductor device according to the present invention, an electrode layer and a recessed part are formed on a surface of a semiconductor substrate. Further, in the semiconductor substrate, a RESURF layer that is in contact with a bottom surface of the recessed part and the electrode layer is formed. In addition, an insulating film is formed on an upper surface of the semiconductor substrate so as to fill the recessed part. Moreover, a field plate electrode is formed on the insulating film above the recessed part.
    Type: Application
    Filed: July 28, 2010
    Publication date: April 14, 2011
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Shigeto Honda, Atsushi Narazaki, Kaoru Motonami
  • Patent number: 7923767
    Abstract: Shallow trench isolation regions are positioned between NAND strings (or other types of non-volatile storage). These isolation regions include sections that form concave cut-out shapes in the substrate for the NAND string (or other types of non-volatile storage). The floating gates (or other charge storage devices) of the NAND strings hang over the sections of the isolation region that form the concave cut-out shape in the substrate. To manufacture such a structure, a two step etching process is used to form the isolation regions. In the first step, isotropic etching is used to remove substrate material in multiple directions, including removing substrate material underneath the floating gates. In the second step, anisotropic etching is used to create the lower part of the isolation region.
    Type: Grant
    Filed: December 26, 2007
    Date of Patent: April 12, 2011
    Assignee: SanDisk Corporation
    Inventor: Masaaki Higashitani
  • Patent number: 7915705
    Abstract: A SiC semiconductor device includes: a SiC substrate; a SiC drift layer on the substrate having an impurity concentration lower than the substrate; a semiconductor element in a cell region of the drift layer; an outer periphery structure including a RESURF layer in a surface portion of the drift layer and surrounding the cell region; and an electric field relaxation layer in another surface portion of the drift layer so that the electric field relaxation layer is separated from the RESURF layer. The electric field relaxation layer is disposed on an inside of the RESURF layer so that the electric field relaxation layer is disposed in the cell region. The electric field relaxation layer has a ring shape.
    Type: Grant
    Filed: March 25, 2008
    Date of Patent: March 29, 2011
    Assignee: Denso Corporation
    Inventors: Takeo Yamamoto, Eiichi Okuno
  • Patent number: 7906388
    Abstract: A semiconductor device is formed by forming a second trench 120 at the base of a first trench 18, depositing insulator 124 at the base of the second trench 120, and then etching cavities 26 laterally from the sidewalls of the second trench, but not the base which is protected by insulator 124. The invention may in particular be used to form semiconductor devices with cavities under the active components, or by filling the cavities to form silicon on insulator or silicon on conductor devices.
    Type: Grant
    Filed: April 12, 2006
    Date of Patent: March 15, 2011
    Assignee: NXP B.V.
    Inventor: Jan Sonsky
  • Patent number: 7897998
    Abstract: A power semiconductor device that includes common conduction regions, charge compensation regions, each adjacent a respective common conduction region, and a stand off region over the common conduction regions and charge compensation regions.
    Type: Grant
    Filed: September 6, 2007
    Date of Patent: March 1, 2011
    Assignee: International Rectifier Corporation
    Inventor: Robert Beach
  • Patent number: 7888735
    Abstract: Complementary RF LDMOS transistors have gate electrodes over split gate oxides. A source spacer of a second conductivity type extends laterally from the source tap of a first conductivity type to approximately the edge of the gate electrode above the thinnest gate oxide. A body of a first conductivity type extends from approximately the bottom center of the source tap to the substrate surface and lies under most of the thin section of the split gate oxide. The source spacer is approximately the length of the gate sidewall oxide and is self aligned with gate electrode. The body is also self aligned with gate electrode. The drain is surrounded by at least one buffer region which is self aligned to the other edge of the gate electrode above the thickest gate oxide and extends to the below the drain and extends laterally under the thickest gate oxide. Both the source tap and drain are self aligned with the gate side wall oxides and are thereby spaced apart laterally from the gate electrode.
    Type: Grant
    Filed: September 3, 2009
    Date of Patent: February 15, 2011
    Assignee: Fairchild Semiconductor Corporation
    Inventor: Jun Cai
  • Patent number: 7880260
    Abstract: A semiconductor device includes an active region with a vertical drift path of a first conduction type and with a near-surface lateral well of a second, complementary conduction type. In addition, the semiconductor device has an edge region surrounding the active region. This edge region has a variable lateral doping material zone of the second conduction type, which adjoins the well. A transition region in which the concentration of doping material gradually decreases from the concentration of the well to the concentration at the start of the variable lateral doping material zone is located between the lateral well and the variable lateral doping material zone.
    Type: Grant
    Filed: April 22, 2008
    Date of Patent: February 1, 2011
    Assignee: Infineon Technology Austria AG
    Inventors: Elmar Falck, Josef Bauer, Gerhard Schmidt
  • Patent number: 7868378
    Abstract: An LDMOS transistor includes a gate including a conductive material over an insulator material, a source including a first impurity region and a second impurity region, a third impurity region, and a drain including a fourth impurity region and a fifth impurity region. The first impurity region is of a first type, and the second impurity region is of an opposite second type. The third impurity region extends from the source region under the gate and is of the first type. The fourth impurity region is of the second type, the fifth impurity region is of the second type, and the fourth impurity region impinges the third impurity region.
    Type: Grant
    Filed: July 17, 2006
    Date of Patent: January 11, 2011
    Assignee: Volterra Semiconductor Corporation
    Inventors: Marco A. Zuniga, Budong You, Yang Lu
  • Patent number: 7863682
    Abstract: A semiconductor device having a junction barrier Schottky diode includes: a SiC substrate; a drift layer on the substrate; an insulation film on the drift layer having an opening in a cell region; a Schottky barrier diode having a Schottky electrode contacting the drift layer through the opening of the insulation film and an ohmic electrode on the substrate; a terminal structure having a RESURF layer surrounding the cell region; and multiple second conductive type layers on an inner side of the RESURF layer. The second conductive type layers and the drift layer provide a PN diode. The Schottky electrode includes a first Schottky electrode contacting the second conductive type layers with ohmic contact and a second Schottky electrode contacting the drift layer with Schottky contact.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: January 4, 2011
    Assignee: Denso Corporation
    Inventors: Eiichi Okuno, Takeo Yamamoto
  • Patent number: 7851883
    Abstract: This invention aims at providing an inexpensive semiconductor device having a parasitic diode and lowering an hfe of a parasitic PNP transistor and a manufacturing method thereof. Such semiconductor device includes a P-type silicon substrate and a gate electrode formed above the P-type silicon substrate. The P-type silicon substrate includes an N-type well layer, an N-type buried layer, a P-type body layer, an N-type source layer formed in the P-type body layer, and a drain contact layer formed in the N-type well layer. The P-type body layer and the N-type source layer are formed by self alignment that uses the gate electrode as a mask. The N-type drain contact layer is formed opposite the N-type source layer across the P-type body layer formed below the gate electrode. The N-type buried layer is formed below the P-type body layer.
    Type: Grant
    Filed: March 10, 2005
    Date of Patent: December 14, 2010
    Assignee: Panasonic Corporation
    Inventors: Masaki Inoue, Akira Ohdaira
  • Patent number: 7851314
    Abstract: A short channel Lateral MOSFET (LMOS) and method are disclosed with interpenetrating drain-body protrusions (IDBP) for reducing channel-on resistance while maintaining high punch-through voltage. The LMOS includes lower device bulk layer; upper source and upper drain region both located atop lower device bulk layer; both upper source and upper drain region are in contact with an intervening upper body region atop lower device bulk layer; both upper drain and upper body region are shaped to form a drain-body interface; the drain-body interface has an IDBP structure with a surface drain protrusion lying atop a buried body protrusion while revealing a top body surface area of the upper body region; gate oxide-gate electrode bi-layer disposed atop the upper body region forming an LMOS with a short channel length defined by the horizontal length of the top body surface area delineated between the upper source region and the upper drain region.
    Type: Grant
    Filed: April 30, 2008
    Date of Patent: December 14, 2010
    Assignee: Alpha and Omega Semiconductor Incorporated
    Inventors: Shekar Mallikarjunaswamy, Amit Paul
  • Patent number: 7851857
    Abstract: A dual current path LDMOSFET transistor (40) is provided which includes a substrate (400), a graded buried layer (401), an epitaxial drift region (404) in which a drain region (416) is formed, a first well region (406) in which a source region (412) is formed, a gate electrode (420) formed adjacent to the source region (412) to define a first channel region (107), and a current routing structure that includes a buried RESURF layer (408) in ohmic contact with a second well region (414) formed in a predetermined upper region of the epitaxial layer (404) so as to be completely covered by the gate electrode (420), the current routing structure being spaced apart from the first well region (406) and from the drain region (416) on at least a side of the drain region to delineate separate current paths from the source region and through the epitaxial layer.
    Type: Grant
    Filed: July 30, 2008
    Date of Patent: December 14, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Yue Fu, Ronghua Zhu, Vishnu K. Khemka, Amitava Bose, Todd C. Roggenbauer
  • Patent number: 7825017
    Abstract: A silicon carbide semiconductor device provided as a semiconductor chip includes a substrate, a drift layer on the substrate, an insulation film on the drift layer, a semiconductor element formed in a cell region of the drift layer, a surface electrode formed on the drift layer and electrically coupled to the semiconductor element through an opening of the insulation film, and a passivation film formed above the drift layer around the periphery of the cell region to cover an outer edge of the surface electrode. The passivation film has an opening through which the surface electrode is exposed outside. A surface of the passivation film is made uneven to increase a length from an inner edge of the opening of the passivation film to a chip edge measured along the surface of the passivation film.
    Type: Grant
    Filed: March 18, 2009
    Date of Patent: November 2, 2010
    Assignees: DENSO CORPORATION, Toyota Jidosha Kabushiki Kaisha
    Inventors: Takeo Yamamoto, Takeshi Endo, Eiichi Okuno, Masaki Konishi
  • Publication number: 20100264489
    Abstract: A transistor contains a first semiconductor layer of a first conductivity type and a drift layer having a pillar structure in which a second semiconductor layer of the first conductivity type and a third semiconductor layer of a second conductivity type are alternately disposed in a direction parallel to a surface of the first semiconductor layer. The fourth semiconductor layer of the first conductivity type and the fifth semiconductor layer of the second conductivity type are alternately disposed and parallel to the drift layer. The fifth semiconductor layer has a larger amount of impurities than the fourth semiconductor layer. The sixth semiconductor layer of the first conductivity type and the seventh semiconductor layer of the second conductivity type are alternately disposed and parallel to the fourth and the fifth semiconductor layers. The seventh semiconductor layer has a smaller amount of impurities than the sixth semiconductor layer.
    Type: Application
    Filed: March 8, 2010
    Publication date: October 21, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hiroshi OHTA, Wataru SAITO, Syotaro ONO, Munehisa YABUZAKI, Nana HATANO, Miho WATANABE
  • Patent number: 7816756
    Abstract: A power semiconductor device includes: a second semiconductor layer of the first conductivity type and a third semiconductor layer of a second conductivity type formed on a first semiconductor layer and alternately arranged along at least one direction parallel to an upper face of the first semiconductor layer; a fourth semiconductor layer of the second conductivity type selectively formed in an upper face of the second and third semiconductor layers; and a control electrode formed above the second, third and fourth semiconductor layers via a gate insulating film. The control electrode includes: first portions periodically arranged along a first direction selected from arranging directions of the third semiconductor layer, the third semiconductor layer has a shortest arrangement period in the first direction, and second portions periodically arranged along a second direction, the second direction being parallel to the upper face of the first semiconductor layer and crossing the first direction.
    Type: Grant
    Filed: March 29, 2007
    Date of Patent: October 19, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Wataru Saito
  • Patent number: 7816733
    Abstract: A semiconductor device having a JBS diode includes: a SiC substrate; a drift layer on the substrate; an insulation film on the drift layer having an opening in a cell region; a Schottky barrier diode having a Schottky electrode contacting the drift layer through the opening and an ohmic electrode on the substrate; a terminal structure having a RESURF layer in the drift layer surrounding the cell region; and multiple second conductive type layers in the drift layer on an inner side of the RESURF layer contacting the Schottky electrode. The second conductive type layers are separated from each other. The second conductive type layers and the drift layer provide a PN diode. Each second conductive type layer has a depth larger than the RESURF layer.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: October 19, 2010
    Assignee: DENSO CORPORATION
    Inventors: Eiichi Okuno, Takeo Yamamoto
  • Patent number: 7812402
    Abstract: In the upper surface of a p? substrate, an n-type impurity region is formed. In the upper surface of the n-type impurity region, a p-well is formed. Also in the upper surface of the n-type impurity region, a p+-type source region and a p+-type drain region are formed. In the upper surface of the p-well, an n+-type drain region and an n+-type source region are formed. In the p? substrate, an n+ buried layer having an impurity concentration higher than that of the n-type impurity region is formed. The n+ buried layer is formed in contact with the bottom surface of the n-type impurity region at a greater depth than the n-type impurity region.
    Type: Grant
    Filed: August 2, 2005
    Date of Patent: October 12, 2010
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kazurnari Hatade
  • Publication number: 20100252904
    Abstract: A semiconductor includes an N-type impurity region provided in a substrate. A P-type RESURF layer is provided at a top face of the substrate in the N-type impurity region. A P-well has an impurity concentration higher than that of the P-type RESURF layer, and makes contact with the P-type RESURF layer at the top face of the substrate in the N-type impurity region. A first high-voltage-side plate is electrically connected to the N-type impurity region, and a low-voltage-side plate is electrically connected to a P-type impurity region. A lower field plate is capable of generating a lower capacitive coupling with the substrate. An upper field plate is located at a position farther from the substrate than the lower field plate, and is capable of generating an upper capacitive coupling with the lower field plate whose capacitance is greater than the capacitance of the lower capacitive coupling.
    Type: Application
    Filed: January 11, 2010
    Publication date: October 7, 2010
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Tetsuo Takahashi, Takami Otsuki
  • Patent number: 7804150
    Abstract: A field effect transistor includes a trench gate extending into a semiconductor region. The trench gate has a front wall facing a drain region and a side wall perpendicular to the front wall. A channel region extends along the side wall of the trench gate, and a drift region extends at least between the drain region and the trench gate. The drift region includes a stack of alternating conductivity type silicon layers.
    Type: Grant
    Filed: June 29, 2006
    Date of Patent: September 28, 2010
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Chang-ki Jeon, Gary Dolny
  • 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
  • Publication number: 20100193895
    Abstract: An integrated circuit device comprising a diode and a method of making an integrated circuit device comprising a diode are provided. The diode can comprise an island of a first conductivity type, a first region of a second conductivity type formed in the island, and a cathode diffusion contact region doped to the second conductivity type disposed in the first region. The diode can also comprise a cathode contact electrically contacting the cathode diffusion contact region, an anode disposed in the island, an anode contact electrically contacting the anode, and a first extension region doped to the first conductivity type disposed at a surface junction between the first region and the island.
    Type: Application
    Filed: April 6, 2010
    Publication date: August 5, 2010
    Inventor: James Douglas Beasom
  • Patent number: 7768093
    Abstract: A semiconductor device has a heavily doped substrate and an upper layer with doped silicon of a first conductivity type disposed on the substrate, the upper layer having an upper surface and including an active region that comprises a well region of a second, opposite conductivity type. An edge termination zone has a junction termination extension (JTE) region of the second conductivity type, the region having portions extending away from the well region and a number of field limiting rings of the second conductivity type disposed at the upper surface in the junction termination extension region.
    Type: Grant
    Filed: March 13, 2009
    Date of Patent: August 3, 2010
    Assignee: Infineon Technologies Austria AG
    Inventors: Hans-Joachim Schulze, Frank Hille, Thomas Raker
  • Patent number: 7759759
    Abstract: An integrated circuit includes a high voltage NPN bipolar transistor and a low voltage device. The NPN bipolar transistor includes a lightly doped p-well as the base region of the transistor while the low voltage devices are built using standard, more heavily doped p-wells. By using a process including a lightly doped p-well and a standard p-well, high and low voltage devices can be integrated onto the same integrated circuit. In one embodiment, the lightly doped p-well and the standard p-well are formed by performing ion implantation using a first dose to form the lightly doped p-well, masking the lightly doped p-well, and performing ion implantation using a second dose to form the standard p-well. The second dose is the difference of the dopant concentrations of the lightly doped p-well and the standard p-well. Other high voltage devices can also be built by incorporating the lightly doped p-well structure.
    Type: Grant
    Filed: July 25, 2005
    Date of Patent: July 20, 2010
    Assignee: Micrel Incorporated
    Inventor: Hideaki Tsuchiko
  • Patent number: 7741695
    Abstract: Extending from an upper surface of an n? semiconductor layer on a p? semiconductor substrate to the interface between the n? semiconductor layer and the p? semiconductor substrate, a p+ impurity region is provided. The p+ impurity region defines a high-potential island region, a low-potential island region and a slit region in the n? semiconductor layer. The n? semiconductor layer in the high-potential island region and the n? semiconductor layer in the low-potential island region are connected by the n? semiconductor layer in the slit region, and a logic circuit is formed in the n? semiconductor layer in the high-potential island region. A width in the direction of Y axis of the n? semiconductor layer in the slit region is set to be narrower than a width in the direction of the Y axis of the n? semiconductor layer in the high-potential island region.
    Type: Grant
    Filed: August 17, 2004
    Date of Patent: June 22, 2010
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kazuhiro Shimizu
  • Patent number: 7732821
    Abstract: The SiC semiconductor device includes a substrate of a first conduction type made of silicon carbide, a drift layer of the first conduction type made of silicon carbide, the drift layer being less doped than the substrate, a cell portion constituted by a part of the substrate and a part of the drift layer, a circumferential portion constituted by another part of the substrate and another part of the drift layer, the circumferential portion being formed so as to surround the cell portion, and a RESURF layer of a second conduction type formed in a surface portion of the drift layer so as to be located in the circumferential portion. The RESURF layer is constituted by first and second RESURF layers having different impurity concentrations, the second RESURF layer being in contact with an outer circumference of the first RESURF layer and extending to a circumference of the cell portion.
    Type: Grant
    Filed: March 11, 2008
    Date of Patent: June 8, 2010
    Assignee: DENSO CORPORATION
    Inventors: Naohiro Suzuki, Tsuyoshi Yamamoto, Toshiyuki Morishita
  • Patent number: 7719029
    Abstract: A single-photon avalanche detector is disclosed that is operable at wavelengths greater than 1000 nm and at operating speeds greater than 10 MHz. The single-photon avalanche detector comprises a thin-film resistor and avalanche photodiode that are monolithically integrated such that little or no additional capacitance is associated with the addition of the resistor.
    Type: Grant
    Filed: May 17, 2007
    Date of Patent: May 18, 2010
    Assignee: Princeton Lightwave, Inc.
    Inventor: Mark Allen Itzler