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)
  • Publication number: 20150001668
    Abstract: According to one embodiment, a semiconductor device is provided. The semiconductor device has a first region formed of semiconductor and a second region formed of semiconductor which borders the first region. An electrode is formed to be in ohmic-connection with the first region. A third region is formed to sandwich the first region. A first potential difference is produced between the first and the second regions in a thermal equilibrium state, according to a second potential difference between the third region and the first region.
    Type: Application
    Filed: September 16, 2014
    Publication date: January 1, 2015
    Inventor: Mitsuhiko KITAGAWA
  • Patent number: 8916913
    Abstract: The present disclosure discloses a high voltage semiconductor device and the associated methods of manufacturing. In one embodiment, the high voltage semiconductor device comprises: an epitaxial layer, a first low voltage well formed in the epitaxial layer; a second low voltage well formed in the epitaxial layer; a high voltage well formed in the epitaxial layer, wherein the second low voltage well is surrounded by the high voltage well; a first highly doping region formed in the first low voltage well; a second highly doping region and a third highly doping region formed in the second low voltage well, wherein the third highly doping region is adjacent to the second highly doping region; a field oxide formed in the epitaxial layer as a shallow-trench isolation structure; and a gate region formed on the epitaxial layer.
    Type: Grant
    Filed: July 13, 2012
    Date of Patent: December 23, 2014
    Assignee: Monolithic Power Systems, Inc.
    Inventors: Ji-Hyoung Yoo, Lei Zhang
  • Publication number: 20140353794
    Abstract: A semiconductor arrangement is provided comprising a guard region. The semiconductor arrangement comprises an active region disposed on a first side of the guard region. The active region comprises an active device. The guard region of the semiconductor arrangement comprises residue from the active region. A method of forming a semiconductor arrangement is also provided.
    Type: Application
    Filed: June 11, 2013
    Publication date: December 4, 2014
    Inventors: Harry-Hak-Lay Chuang, Wei Cheng Wu, Chin-Yi Huang, Shih-Chang Liu
  • Publication number: 20140346633
    Abstract: A semiconductor device includes a high voltage isolation structure having a double RESURF structure. The high voltage isolation structure separates a low potential region from a high potential region. The high voltage isolation structure has an annular strip shape in a plan view and includes a straight portion and a corner portion which is connected to the straight portion. In the high voltage isolation structure, a p-type RESURF region is formed in a surface layer of a front surface of a substrate in an n-type well region along the outer circumference of the n-type well region. In the corner portion, the total amount of impurities per unit area in the RESURF region is less than that in the straight portion.
    Type: Application
    Filed: August 11, 2014
    Publication date: November 27, 2014
    Inventors: Akihiro JONISHI, Masaharu YAMAJI
  • Publication number: 20140327104
    Abstract: A super junction semiconductor device includes a layered compensation structure with an n-type compensation layer and a p-type compensation layer, a dielectric layer facing the p-type layer, and an intermediate layer interposed between the dielectric layer and the p-type compensation layer. The layered compensation structure and the intermediate layer are provided such that when a reverse blocking voltage is applied between the n-type and p-type compensation layers, holes accelerated in the direction of the dielectric layer have insufficient energy to be absorbed and incorporated into the dielectric material. Since the dielectric layer absorbs and incorporates significantly less holes than without the intermediate layer, the breakdown voltage remains stable over a long operation time.
    Type: Application
    Filed: May 1, 2013
    Publication date: November 6, 2014
    Inventors: Armin Willmeroth, Stefan Gamerith, Markus Schmitt, Bjoern Fischer
  • Patent number: 8878330
    Abstract: An integrated circuit containing a voltage divider having an upper resistor of unsilicided gate material over field oxide around a central opening and a drift layer under the upper resistor, an input terminal coupled to an input node of the upper resistor adjacent to the central opening in the field oxide and coupled to the drift layer through the central opening, a sense terminal coupled to a sense node on the upper resistor opposite from the input node, a lower resistor with a sense node coupled to the sense terminal and a reference node, and a reference terminal coupled to the reference node. A process of forming the integrated circuit containing the voltage divider.
    Type: Grant
    Filed: August 6, 2012
    Date of Patent: November 4, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: Hideaki Kawahara, Marie Denison, Sameer Pendharkar, Philip L. Hower, John Lin, Robert A. Neidorff
  • Patent number: 8866221
    Abstract: A drift layer of a super junction semiconductor device includes first portions of a first conductivity type and second portions of a second conductivity type opposite to the first conductivity type. The first and second portions are formed both in a cell area and in an edge area surrounding the cell area, wherein an on-state or forward current through the drift layer flows through the first portions in the cell area. At least one of the first and second portions other than the first portions in the cell area includes an auxiliary structure or contains auxiliary impurities to locally reduce the avalanche rate. Locally reducing the avalanche rate increases the total voltage blocking capability of the super junction semiconductor device.
    Type: Grant
    Filed: July 2, 2012
    Date of Patent: October 21, 2014
    Assignee: Infineon Technologies Austria AG
    Inventors: Franz Hirler, Hans Weber, Hans-Joachim Schulze, Uwe Wahl
  • Patent number: 8866252
    Abstract: We describe a RESURF semiconductor device having an n-drift region with a p-top layer and in which a MOS (Metal Oxide Semiconductor) channel of the device is formed within the p-top layer.
    Type: Grant
    Filed: September 15, 2011
    Date of Patent: October 21, 2014
    Assignee: Cambridge Semiconductor Limited
    Inventors: Tanya Trajkovic, Florin Udrea, Vasantha Pathirana, Nishad Udugampola
  • Publication number: 20140299962
    Abstract: A semiconductor device includes: a layer of a first conductivity type; a well of a second conductivity type on the layer of the first conductivity type in an active region; and a flat RESURF layer of the second conductivity type on the layer of the first conductivity type on an outer circumference of the well as a termination structure. The RESURF layer includes a low concentration layer arranged at an inner end on the well side and an outer end on the outer circumferential side, and a high concentration layer arranged between the inner end and the outer end and having a higher impurity concentration than the low concentration layer.
    Type: Application
    Filed: January 8, 2014
    Publication date: October 9, 2014
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventor: Tetsuo TAKAHASHI
  • Patent number: 8847307
    Abstract: Power devices using refilled trenches with permanent charge at or near their sidewalls. These trenches extend vertically into a drift region.
    Type: Grant
    Filed: December 4, 2012
    Date of Patent: September 30, 2014
    Assignee: MaxPower Semiconductor, Inc.
    Inventors: Mohamed N. Darwish, Jun Zeng, Richard A. Blanchard
  • Patent number: 8841744
    Abstract: A semiconductor apparatus having a bootstrap-type driver circuit includes a cavity for a SON structure formed below a bootstrap diode Db, and a p-type floating region formed in a n? epitaxial layer between a bootstrap diode Db and a p-type GND region at the ground potential (GND). The p-type floating region extends to the cavity for suppressing the leakage current caused by the holes flowing to the p? substrate in charging an externally attached bootstrap capacitor C1. The semiconductor apparatus which includes a bootstrap-type driver circuit facilitates suppressing the leakage current caused by the holes flowing to the p? substrate, when the bootstrap diode is biased in forward.
    Type: Grant
    Filed: April 17, 2012
    Date of Patent: September 23, 2014
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Tomohiro Imai, Masaharu Yamaji
  • Publication number: 20140246750
    Abstract: Proton irradiation is performed a plurality of times from rear surface of an n-type semiconductor substrate, which is an n? drift layer, forming an n-type FS layer having lower resistance than the n-type semiconductor substrate in the rear surface of the n? drift layer. When the proton irradiation is performed a plurality of times, the next proton irradiation is performed to as to compensate for a reduction in mobility due to disorder which remains after the previous proton irradiation. In this case, the second or subsequent proton irradiation is performed at the position of the disorder which is formed by the previous proton irradiation. In this way, even after proton irradiation and a heat treatment, the disorder is reduced and it is possible to prevent deterioration of characteristics, such as increase in leakage current. It is possible to form an n-type FS layer including a high-concentration hydrogen-related donor layer.
    Type: Application
    Filed: May 13, 2014
    Publication date: September 4, 2014
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Hiroshi TAKISHITA, Takashi YOSHIMURA, Masayuki MIYAZAKI, Hidenao KURIBAYASHI
  • Patent number: 8823051
    Abstract: A diode-connected lateral transistor on a substrate of a first conductivity type includes a vertical parasitic transistor through which a parasitic substrate leakage current flows. Means for shunting at least a portion of the flow of parasitic substrate leakage current away from the vertical parasitic transistor is provided.
    Type: Grant
    Filed: May 15, 2006
    Date of Patent: September 2, 2014
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Jun Cai, Micheal Harley-Stead, Jim G. Holt
  • Patent number: 8786046
    Abstract: A semiconductor device which solves the following problem of a super junction structure: due to a relatively high concentration in the body cell region (active region), in peripheral areas (peripheral regions or junction end regions), it is difficult to achieve a breakdown voltage equivalent to or higher than in the cell region through a conventional junction edge terminal structure or resurf structure. The semiconductor device includes a power MOSFET having a super junction structure formed in the cell region by a trench fill technique. Also, super junction structures having orientations parallel to the sides of the cell region are provided in a drift region around the cell region.
    Type: Grant
    Filed: June 5, 2013
    Date of Patent: July 22, 2014
    Assignee: Renesas Electronics Corporation
    Inventors: Tomohiro Tamaki, Yoshito Nakazawa, Satoshi Eguchi
  • Patent number: 8772869
    Abstract: A power semiconductor device includes: a first semiconductor layer; second and third semiconductor layers above and alternatively arranged along a direction parallel to an upper surface of the first semiconductor layer; and plural fourth semiconductor layers provided on some of immediately upper regions of the third semiconductor layer. An array period of the fourth semiconductor layers is larger than that of the second semiconductor layer. A thickness of part of the gate insulating film in an immediate upper region of a central portion between the fourth semiconductor layers is thicker than a thickness of part of the gate insulating film in an immediate upper region of the fourth semiconductor layers. Sheet impurity concentrations of the second and third semiconductor layers in the central portion are higher than a sheet impurity concentration of the third semiconductor layer in an immediately lower region of the fourth semiconductor layers.
    Type: Grant
    Filed: March 18, 2008
    Date of Patent: July 8, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Wataru Saito, Syotaro Ono
  • Publication number: 20140159152
    Abstract: A power semiconductor device is provided, which can prevent an electric field from concentrating on a diode region, and can improve a breakdown voltage by creating an impurity concentration gradient in the diode region to increase from a termination region to an active cell region to cause reverse current to be distributed to the active cell region.
    Type: Application
    Filed: November 7, 2013
    Publication date: June 12, 2014
    Applicant: KEC Corporation
    Inventor: Tae Wan Kim
  • Patent number: 8749017
    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: Grant
    Filed: March 23, 2011
    Date of Patent: June 10, 2014
    Assignee: Fuji Electric Co., Ltd
    Inventor: Hong-fei Lu
  • Patent number: 8742501
    Abstract: A power semiconductor device that realizes high-speed turnoff and soft switching at the same time has an n-type main semiconductor layer that includes lightly doped n-type semiconductor layers and extremely lightly doped n-type semiconductor layers arranged alternately and repeatedly between a p-type channel layer and an n+-type field stop layer, in a direction parallel to the first major surface of the n-type main semiconductor layer. A substrate used for manufacturing the semiconductor device is fabricated by forming trenches in an n-type main semiconductor layer 1 and performing ion implantation and subsequent heat treatment to form an n+-type field stop layer in the bottom of the trenches. The trenches are then filled with a semiconductor doped more lightly than the n-type main semiconductor layer for forming extremely lightly doped n-type semiconductor layers. The manufacturing method is applicable with variations to various power semiconductor devices such as IGBT's, MOSFET's and PIN diodes.
    Type: Grant
    Filed: July 25, 2012
    Date of Patent: June 3, 2014
    Assignee: Fuji Electric Co., Ltd.
    Inventor: Koh Yoshikawa
  • Patent number: 8716746
    Abstract: In a semiconductor device, an IGBT cell includes a trench passing through a base layer of a semiconductor substrate to a drift layer of the semiconductor substrate, a gate insulating film on an inner surface of the trench, a gate electrode on the gate insulating film, a first conductivity-type emitter region in a surface portion of the base layer, and a second conductivity-type first contact region in the surface portion of the base layer. The IGBT cell further includes a first conductivity-type floating layer disposed within the base layer to separate the base layer into a first portion including the emitter region and the first contact region and a second portion adjacent to the drift layer, and an interlayer insulating film disposed to cover an end of the gate electrode. A diode cell includes a second conductivity-type second contact region in the surface portion of the base layer.
    Type: Grant
    Filed: August 9, 2011
    Date of Patent: May 6, 2014
    Assignees: DENSO CORPORATION, Toyota Jidosha Kabushiki Kaisha
    Inventors: Masaki Koyama, Yasushi Ookura, Akitaka Soeno, Tatsuji Nagaoka, Takahide Sugiyama, Sachiko Aoi, Hiroko Iguchi
  • Publication number: 20140110815
    Abstract: A trench-isolated RESURF diode structure (100) is provided which includes a substrate (150) in which is formed anode (130, 132) and cathode (131) contact regions separated from one another by a shallow trench isolation region (114, 115), along with a non-uniform cathode region (104) and peripheral anode regions (106, 107) which define vertical and horizontal p-n junctions under the anode contact regions (130, 132), including a horizontal cathode/anode junction that is shielded by the heavily doped anode contact region (132).
    Type: Application
    Filed: October 19, 2012
    Publication date: April 24, 2014
    Applicant: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Xin Lin, Hongning Yang, Jiang-Kai Zuo
  • Patent number: 8692324
    Abstract: A laterally diffused metal-oxide-semiconductor transistor device includes a substrate having a first conductivity type with a semiconductor layer formed over the substrate. A source region and a drain extension region of the first conductivity type are formed in the semiconductor layer. A body region of a second conductivity type is formed in the semiconductor layer. A conductive gate is formed over a gate dielectric layer that is formed over a channel region. A drain contact electrically connects the drain extension region to the substrate and is laterally spaced from the channel region. The drain contact includes a highly-doped drain contact region formed between the substrate and the drain extension region in the semiconductor layer, wherein a topmost portion of the highly-doped drain contact region is spaced from the upper surface of the semiconductor layer. A source contact electrically connects the source region to the body region.
    Type: Grant
    Filed: June 16, 2008
    Date of Patent: April 8, 2014
    Assignee: Ciclon Semiconductor Device Corp.
    Inventors: Jacek Korec, Shuming Xu, Christopher Boguslaw Kocon
  • Patent number: 8686498
    Abstract: A semiconductor device is provided. The semiconductor device includes a gate on a substrate, a source region at a first side of the gate, a first conductive type body region under the source region, a second conductive type drain region at a second side of the gate, a device isolation region in the substrate between the source region and the drain region and overlapping part of the gate, and a first buried layer extending in a direction from the source region to the drain region, the first buried layer under the body region, overlapping part of the device isolation region, and not overlapping the drain region.
    Type: Grant
    Filed: March 2, 2011
    Date of Patent: April 1, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Mueng-Ryul Lee
  • Patent number: 8643137
    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: June 4, 2012
    Date of Patent: February 4, 2014
    Assignee: Alpha & Omega Semiconductor, Inc.
    Inventors: Shekar Mallikarjunaswamy, Amit Paul
  • Patent number: 8643136
    Abstract: The present invention discloses a high voltage device and a manufacturing method thereof. The high voltage device includes: a first conductive type substrate in which isolation regions are formed for defining a device region; a gate formed on the first conductive type substrate; a source and a drain formed in the device region and located at both sides of the gate respectively, and doped with second conductive type impurities; a second conductive type well, which is formed in the first conductive type substrate, and surrounds the drain from top view; and a first deep trench isolation structure, which is formed in the first conductive type substrate, and is located in the second conductive type well between the source and the drain from top view, wherein the depth of the first deep trench isolation structure is deeper than the second conductive type well from the cross-sectional view.
    Type: Grant
    Filed: March 1, 2011
    Date of Patent: February 4, 2014
    Assignee: Richtek Technology Corporation
    Inventors: Tsung-Yi Huang, Kuo-Hsuan Lo
  • Patent number: 8618627
    Abstract: A semiconductor device can include a transistor and an isolation region. The transistor is formed in a semiconductor substrate having a first conductivity type. The transistor includes a drift region extending from a drain region toward a source region and having a second conductivity type. The drift region includes a first resurf region near a working top surface and having the first conductivity type. The high voltage isolation island region includes a first well region laterally offset from the drift region. The first well region has the second conductivity type. An isolation region is located laterally between the drain region and the first well region. The isolation region comprises a portion of the semiconductor substrate extending to the top working surface.
    Type: Grant
    Filed: June 24, 2010
    Date of Patent: December 31, 2013
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Sunglyong Kim, Jongjib Kim
  • Publication number: 20130334648
    Abstract: High voltage diodes are disclosed. A semiconductor device is provided having a P well region; an N well region adjacent to the P well region and forming a p-n junction with the P well region; a P+ region forming an anode at the upper surface of the semiconductor substrate in the P well region; an N+ region forming a cathode at the upper surface of the semiconductor substrate in the N well region; and an isolation structure formed over the upper surface of the semiconductor substrate between the anode and the cathode and electrically isolating the anode and cathode including a first dielectric layer overlying a portion of the upper surface of the semiconductor substrate, and a second dielectric layer overlying a portion of the first dielectric layer and a portion of the upper surface of the semiconductor substrate. Methods for forming the devices are disclosed.
    Type: Application
    Filed: June 15, 2012
    Publication date: December 19, 2013
    Applicant: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
    Inventors: Wan-Yen Lin, Yi-Feng Chang, Jam-Wem Lee
  • Publication number: 20130334649
    Abstract: In a semiconductor body, a semiconductor device has an active region with a vertical drift section of a first conduction type and a near-surface lateral well of a second, complementary conduction type. An edge region surrounding this active region comprises a variably laterally doped doping material zone (VLD zone). This VLD zone likewise has the second, complementary conduction type and adjoins the well. The concentration of doping material of the VLD zone decreases to the concentration of doping material of the drift section along the VLD zone towards a semiconductor chip edge. Between the lateral well and the VLD zone, a transitional region is provided which contains at least one zone of complementary doping located at a vertically lower point than the well in the semiconductor body.
    Type: Application
    Filed: August 14, 2013
    Publication date: December 19, 2013
    Applicant: Infineon Technologies Austria AG
    Inventor: Gerhard Schmidt
  • Patent number: 8592903
    Abstract: A bipolar semiconductor device and manufacturing method. One embodiment provides a diode structure including a structured emitter coupled to a first metallization is provided. The structured emitter includes a first weakly doped semiconductor region of a first conductivity type which forms a pn-load junction with a weakly doped second semiconductor region of the diode structure. The structured emitter includes at least a highly doped first semiconductor island of the first conductivity type which at least partially surrounds a highly doped second semiconductor island of the second conductivity type.
    Type: Grant
    Filed: November 26, 2008
    Date of Patent: November 26, 2013
    Assignee: Infineon Technologies Austria AG
    Inventors: Hans-Joachim Schulze, Frank Pfirsch
  • Patent number: 8564088
    Abstract: In a semiconductor body, a semiconductor device has an active region with a vertical drift section of a first conduction type and a near-surface lateral well of a second, complementary conduction type. An edge region surrounding this active region comprises a variably laterally doped doping material zone (VLD zone). This VLD zone likewise has the second, complementary conduction type and adjoins the well. The concentration of doping material of the VLD zone decreases to the concentration of doping material of the drift section along the VLD zone towards a semiconductor chip edge. Between the lateral well and the VLD zone, a transitional region is provided which contains at least one zone of complementary doping located at a vertically lower point than the well in the semiconductor body.
    Type: Grant
    Filed: August 19, 2008
    Date of Patent: October 22, 2013
    Assignee: Infineon Technologies Austria AG
    Inventor: Gerhard Schmidt
  • Patent number: 8552511
    Abstract: A semiconductor device including a low-concentration impurity region formed on the drain side of an n-type MIS transistor, in a non-self-aligned manner with respect to an end portion of the gate electrode. A high-concentration impurity region is placed with a specific offset from the gate electrode and a sidewall insulating film. The semiconductor device enables the drain breakdown voltage to be sufficient and the on-resistance to decrease. A silicide layer is also formed on the surface of the gate electrode, thereby achieving gate resistance reduction and high frequency characteristics improvement.
    Type: Grant
    Filed: February 8, 2011
    Date of Patent: October 8, 2013
    Assignee: Fujitsu Semiconductor Limited
    Inventor: Masashi Shima
  • Patent number: 8541862
    Abstract: A device includes a semiconductor substrate including a surface, a drain region in the semiconductor substrate having a first conductivity type, a well region in the semiconductor substrate on which the drain region is disposed, the well region having the first conductivity type, a buried isolation layer in the semiconductor substrate extending across the well region, the buried isolation layer having the first conductivity type, a reduced surface field (RESURF) region disposed between the well region and the buried isolation layer, the RESURF region having a second conductivity type, and a plug region in the semiconductor substrate extending from the surface of the substrate to the RESURF region, the plug region having the second conductivity type.
    Type: Grant
    Filed: November 30, 2011
    Date of Patent: September 24, 2013
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Hongning Yang, Jiang-Kai Zuo
  • Patent number: 8502310
    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: Grant
    Filed: October 20, 2009
    Date of Patent: August 6, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Hiromu Shiomi, Kazuhide Sumiyoshi, Yu Saitoh, Makoto Kiyama
  • Patent number: 8492867
    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: Grant
    Filed: June 20, 2011
    Date of Patent: July 23, 2013
    Assignees: DENSO CORPORATION, Toyota Jidosha Kabushiki Kaisha
    Inventors: Kensaku Yamamoto, Naohiro Suzuki, Hidefumi Takaya, Masahiro Sugimoto, Jun Morimoto, Narumasa Soejima, Tsuyoshi Ishikawa, Yukihiko Watanabe
  • Publication number: 20130161645
    Abstract: A semiconductor device includes a semiconductor substrate having a principal surface, and an insulating film formed on the principal surface and continuously covering a top surface of a first boundary region and a top surface of a second boundary region, the first boundary region including a boundary between a well layer and a RESURF layer, the second boundary region including a boundary between the RESURF layer and a first impurity region. The semiconductor device further includes a plurality of lower field plates formed in the insulating film in such a manner that the plurality of lower field plates do not lie directly above the first and second boundary regions, and a plurality of upper field plates formed on the insulating film in such a manner that the plurality of upper field plates do not lie directly above the first and second boundary regions.
    Type: Application
    Filed: September 14, 2012
    Publication date: June 27, 2013
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventor: Tetsuo TAKAHASHI
  • Patent number: 8450183
    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: Grant
    Filed: December 7, 2010
    Date of Patent: May 28, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventors: Ryoichi Fujii, Shigeto Honda, Atsushi Narazaki, Kaoru Motonami
  • Patent number: 8431450
    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: January 10, 2011
    Date of Patent: April 30, 2013
    Assignee: Volterra Semiconductor Corporation
    Inventors: Marco A. Zuniga, Budong You, Yang Lu
  • Publication number: 20130099347
    Abstract: A superjunction semiconductor device is disclosed in which the trade-off relationship between breakdown voltage characteristics and voltage drop characteristics is considerably improved, and it is possible to greatly improve the charge resistance of an element peripheral portion and long-term breakdown voltage reliability. It includes parallel pn layers of n-type drift regions and p-type partition regions in superjunction structure. PN layers are depleted when off-state voltage is applied. Repeating pitch of the second parallel pn layer in a ring-like element peripheral portion encircling the element active portion is smaller than repeating pitch of the first parallel pn layer in the element active portion. Element peripheral portion includes low concentration n-type region on the surface of the second parallel pn layer. The depth of p-type partition region of an outer peripheral portion in the element peripheral portion is smaller than the depth of p-type partition region of an inner peripheral portion.
    Type: Application
    Filed: October 22, 2012
    Publication date: April 25, 2013
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventor: FUJI ELECTRIC CO., LTD.
  • Patent number: 8410557
    Abstract: A P type drift layer is formed in an N type epitaxial layer from under a drain layer to under an N type body layer under a source layer through under an element isolation insulation film. This P type drift layer is shallower immediately under the drain layer than under the element isolation insulation film, and gradually shallows from under the element isolation insulation film to the N type body layer to be in contact with the bottom of the N type body layer. Since the P type drift layer is thus diffused in a wide region, a wide current path is formed from the N type body layer to the drain layer, and the current drive ability is enhanced and the drain breakdown voltage is also increased.
    Type: Grant
    Filed: June 17, 2009
    Date of Patent: April 2, 2013
    Assignee: Semiconductor Components Industries, LLC
    Inventors: Haruki Yoneda, Kazuhiro Sasada
  • Patent number: 8404526
    Abstract: A semiconductor device includes a first conductive type first semiconductor region, a second semiconductor region, and a second conductive type lateral RESURF region. The first semiconductor region is arranged on a first electrode side. The second semiconductor region includes first conductive type first pillar regions and a terminal part. The second pillar regions are alternately arranged on an element part. The terminal part is formed around the element part along a surface of the first semiconductor region on a second electrode side opposite to the first electrode side of the first semiconductor region. Furthermore, the second conductive type lateral RESURF region is formed in the second semiconductor region on the terminal part.
    Type: Grant
    Filed: November 29, 2011
    Date of Patent: March 26, 2013
    Assignee: Sony Corporation
    Inventor: Yuji Sasaki
  • Patent number: 8395230
    Abstract: A semiconductor device includes: a first semiconductor region of a first conductivity type disposed on the side of a first electrode; and a second semiconductor region having first pillar regions of the first conductivity type and second pillar regions of a second conductivity type, the first pillar regions and the second pillar regions being provided in paired state and alternately, in a device portion and a terminal portion surrounding the device portion, along a surface on the side of a second electrode disposed on the opposite side of the first semiconductor region from the first electrode. The semiconductor device further includes a lateral RESURF (reduced surface field) region of the second conductivity type disposed at a surface portion, on the opposite side from the first semiconductor region, of the second semiconductor region in the terminal portion.
    Type: Grant
    Filed: July 7, 2009
    Date of Patent: March 12, 2013
    Assignee: Sony Corporation
    Inventors: Hiroki Hozumi, Yuji Sasaki, Shusaku Yanagawa
  • Patent number: 8384184
    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: Grant
    Filed: September 15, 2010
    Date of Patent: February 26, 2013
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Tahir A. Khan, Bernhard H. Grote, Vishnu K. Khemka, Ronghua Zhu
  • Publication number: 20130037852
    Abstract: Super-junction MOSFETs by trench fill system requires void-free filling epitaxial growth. This may require alignment of plane orientations of trenches in a given direction. Particularly, when column layout at chip corner part is bilaterally asymmetrical with a diagonal line between chip corners, equipotential lines in a blocking state are curved at corner parts due to column asymmetry at chip corner. This tends to cause points where equipotential lines become dense, which may cause breakdown voltage reduction. In the present invention, in power type semiconductor active elements such as power MOSFETs, a ring-shaped field plate is disposed in chip peripheral regions around an active cell region, etc., assuming a nearly rectangular shape. The field plate has an ohmic-contact part in at least a part of the portion along the side of the rectangle. However, in the portion corresponding to the corner part of the rectangle, an ohmic-contact part is not disposed.
    Type: Application
    Filed: July 13, 2012
    Publication date: February 14, 2013
    Applicant: RENESAS ELECTRONICS CORPORATION
    Inventor: Tomohiro TAMAKI
  • Publication number: 20130037851
    Abstract: A semiconductor device including a base semiconductor layer of a first conductivity type, a cell portion including a diffusion region of a second conductivity type formed on a surface of the base semiconductor layer, a plurality of guard ring semiconductor layers of the second conductivity type formed on the surface of the base semiconductor layer, each guard ring semiconductor layer being formed to surround the cell portion, a plurality of first RESURF semiconductor layers of the first conductivity type provided on the surface of the base semiconductor layer inside the plurality of guard ring semiconductor layers and having a higher concentration than the base semiconductor layer and a second RESURF semiconductor layer of the first conductivity type provided on the surface of the base semiconductor layer between the outermost guard ring semiconductor layer and the EQPR semiconductor layer.
    Type: Application
    Filed: March 14, 2012
    Publication date: February 14, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventor: Ryohei GEJO
  • Patent number: 8362586
    Abstract: According to one embodiment, a semiconductor device provided with a structure, which prevents withstand voltage deterioration and may be manufactured at a low cost, is provided.
    Type: Grant
    Filed: September 7, 2010
    Date of Patent: January 29, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Tetsuo Hatakeyama
  • Patent number: 8350353
    Abstract: A method of manufacturing a silicon carbide semiconductor device is provided that includes a step of forming in a surface of a silicon carbide wafer of first conductivity type a first region of second conductivity type having a predetermined space thereinside by ion-implanting aluminum as a first impurity and boron as a second impurity; a step of forming a JTE region in the surface of the silicon carbide wafer from the first region by diffusing the boron ion-implanted in the first region toward its neighboring zones by an activation annealing treatment; a step of forming a first electrode on the surface of the silicon carbide wafer at the space inside the first region and at an inner part of the first region; and a step of forming a second electrode on the opposite surface of the silicon carbide wafer. Thereby, a JTE region can be formed that has a wide range of impurity concentration and a desired breakdown voltage without increasing the number of steps of the manufacturing process.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: January 8, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventor: Yoichiro Tarui
  • Patent number: 8344472
    Abstract: Transistors (21, 41) employing floating buried layers may be susceptible to noise coupling into the floating buried layers. In IGFETS this is reduced or eliminated by providing a normally-ON switch (80, 80?) coupling the buried layer (102, 142, 172, 202) and the IGFET source (22, 42) or drain (24, 44). When the transistor (71, 91) is OFF, this clamps the buried layer voltage and substantially prevents noise coupling thereto. When the drain-source voltage VDS exceeds the switch's (80, 80?) threshold voltage Vt, it turns OFF, allowing the buried layer (102, 142, 172, 202) to float, and thereby resume normal transistor action without degrading the breakdown voltage or ON-resistance. In a preferred embodiment, a normally-ON lateral JFET (801, 801?, 801-1, 801-2, 801-3) conveniently provides this switching function.
    Type: Grant
    Filed: March 30, 2010
    Date of Patent: January 1, 2013
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Vishnu K. Khemka, Tahir A. Khan, Weixiao Huang, Ronghua Zhu
  • Patent number: 8338907
    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: Grant
    Filed: January 20, 2012
    Date of Patent: December 25, 2012
    Assignee: Sanken Electronic Co., Ltd.
    Inventor: Hironori Aoki
  • Patent number: 8330213
    Abstract: Power devices using refilled trenches with permanent charge at or near their sidewalls. These trenches extend vertically into a drift region.
    Type: Grant
    Filed: April 13, 2010
    Date of Patent: December 11, 2012
    Assignee: MaxPower Semiconductor, Inc.
    Inventors: Mohamed N. Darwish, Jun Zeng, Richard A. Blanchard
  • Patent number: RE44720
    Abstract: A method of forming a MOSFET is provided. The method comprises forming a relatively thin layer of dielectric on a substrate. Depositing a gate material layer on the relatively thin layer of dielectric. Removing portions of the gate material layer to form a first and second gate material regions of predetermined lateral lengths. Introducing a first conductivity type dopant in the substrate to form a top gate using first edges of the first and second gate material regions as masks, Introducing a second conductivity dopant of high dopant density in the substrate to form a drain region adjacent the surface of the substrate using a second edge of the second gate material region as a mask to form a first edge of the drain region, wherein a spaced distance between the top gate and the drain region is determined by the lateral length of the second gate material region.
    Type: Grant
    Filed: August 21, 2012
    Date of Patent: January 21, 2014
    Assignee: Intersil Americas Inc.
    Inventor: James D. Beasom
  • Patent number: RE44730
    Abstract: A method of forming a MOSFET is provided. The method comprises forming a relatively thin layer of dielectric on a substrate. Depositing a gate material layer on the relatively thin layer of dielectric. Removing portions of the gate material layer to form a first and second gate material regions of predetermined lateral lengths. Introducing a first conductivity type dopant in the substrate to form a top gate using first edges of the first and second gate material regions as masks, Introducing a second conductivity dopant of high dopant density in the substrate to form a drain region adjacent the surface of the substrate using a second edge of the second gate material region as a mask to form a first edge of the drain region, wherein a spaced distance between the top gate and the drain region is determined by the lateral length of the second gate material region.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: January 28, 2014
    Assignee: Intersil Americas Inc.
    Inventor: James D. Beasom