Schottky Diode (epo) Patents (Class 257/E21.359)
  • Publication number: 20130105820
    Abstract: A Schottky junction type semiconductor device in which the opening width of a trench can be decreased without deteriorating the withstanding voltage. The cross sectional shape of a trench has a shape of a sub-trench in which the central portion is higher and the periphery is lower at the bottom of the trench, and a p type impurity is introduced vertically to the surface of the drift layer thereby forming a p+ SiC region, which is formed in contact to the inner wall of the trench having the sub-trench disposed therein, such that the junction position is formed more deeply in the periphery of the bottom of the trench than the junction position in the central portion of the bottom of the trench.
    Type: Application
    Filed: October 31, 2012
    Publication date: May 2, 2013
    Applicant: HITACHI, LTD.
    Inventor: Hitachi, Ltd.
  • Patent number: 8426893
    Abstract: An epitaxial substrate for electronic devices is provided, which can improve vertical breakdown voltage and provides a method of producing the same. The epitaxial substrate includes a conductive SiC single crystal substrate, a buffer as an insulating layer on the SiC single crystal substrate, and a main laminate formed by epitaxially growing a plurality of Group III nitride layers on the buffer. Further, the buffer includes at least an initial growth layer in contact with the SiC single crystal substrate and a superlattice laminate having a superlattice multi-layer structure on the initial growth layer. The initial growth layer is made of a Ba1Alb1Gac1Ind1N material. Furthermore, the superlattice laminate is configured by alternately stacking a first layer made of a Ba2Alb2Gac2Ind2N material and a second layer made of a Ba3Alb3Gac3Ind3N material having a different band gap from the first layer.
    Type: Grant
    Filed: May 10, 2010
    Date of Patent: April 23, 2013
    Assignee: Dowa Electronics Materials Co., Ltd.
    Inventors: Tetsuya Ikuta, Jo Shimizu, Tomohiko Shibata, Ryo Sakamoto, Tsuneo Ito
  • Patent number: 8405184
    Abstract: A trench Schottky diode and its manufacturing method are provided. The trench Schottky diode includes a semiconductor substrate having therein a plurality of trenches, a gate oxide layer, a polysilicon structure, a guard ring and an electrode. At first, the trenches are formed in the semiconductor substrate by an etching step. Then, the gate oxide layer and the polysilicon structure are formed in the trenches and protrude above a surface of the semiconductor substrate. The guard ring is formed to cover a portion of the resultant structure. At last, the electrode is formed above the guard ring and the other portion not covered by the guard ring. The protruding gate oxide layer and the protruding polysilicon structure can avoid cracks occurring in the trench structure.
    Type: Grant
    Filed: June 28, 2010
    Date of Patent: March 26, 2013
    Assignee: PFC Device Corporation
    Inventors: Kou-Liang Chao, Hung-Hsin Kuo, Tse-Chuan Su, Mei-Ling Chen
  • Publication number: 20130056744
    Abstract: Semiconductor devices with guard rings are described. The semiconductor devices may be, e.g., transistors and diodes designed for high-voltage applications. A guard ring is a floating electrode formed of electrically conducting material above a semiconductor material layer. A portion of an insulating layer is between at least a portion of the guard ring and the semiconductor material layer. A guard ring may be located, for example, on a transistor between a gate and a drain electrode. A semiconductor device may have one or more guard rings.
    Type: Application
    Filed: September 6, 2011
    Publication date: March 7, 2013
    Applicant: TRANSPHORM INC.
    Inventors: Umesh Mishra, Srabanti Chowdhury, Yuvaraj Dora
  • Patent number: 8377810
    Abstract: Disclosed is a silicon-on-insulator-based Schottky barrier diode with a low forward voltage that can be manufactured according to standard SOI process flow. An active silicon island is formed using an SOI wafer. One area of the island is heavily-doped with an n-type or p-type dopant, one area is lightly-doped with the same dopant, and an isolation structure is formed on the top surface above a junction between the two areas. A metal silicide region contacts the lightly-doped side of the island forming a Schottky barrier. Another discrete metal silicide region contacts the heavily-doped area of the island forming an electrode to the Schottky barrier (i.e., a Schottky barrier contact). The two metal silicide regions are isolated from each other by the isolation structure. Contacts to each of the discrete metal silicide regions allow a forward and/or a reverse bias to be applied to the Schottky barrier.
    Type: Grant
    Filed: April 18, 2007
    Date of Patent: February 19, 2013
    Assignee: International Business Machines Corporation
    Inventor: Edward J. Nowak
  • Publication number: 20130032821
    Abstract: A Schottky barrier diode (SBD) is provided, which improves electrical characteristics and optical characteristics by securing high crystallinity by including an n-gallium nitride (GaN) layer and a GaN layer which are doped with aluminum (Al). In addition, by providing a p-GaN layer on the Al-doped GaN layer, a depletion layer may be formed when a reverse current is applied, thereby reducing a leakage current. The SBD may be manufactured by etching a part of the Al-doped GaN layer and growing a p-GaN layer from the etched part of the Al-doped GaN layer. Therefore, a thin film crystal is not damaged, thereby increasing reliability. Also, since dedicated processes for ion implantation and thermal processing are not necessary, simplified process and reduced cost may be achieved.
    Type: Application
    Filed: January 17, 2012
    Publication date: February 7, 2013
    Inventor: Jae Hoon LEE
  • Publication number: 20130032809
    Abstract: An electronic device includes a silicon carbide layer including an n-type drift region therein, a contact forming a Schottky junction with the drift region, and a p-type junction barrier region on the silicon carbide layer. The p-type junction barrier region includes a p-type polysilicon region forming a P-N heterojunction with the drift region, and the p-type junction barrier region is electrically connected to the contact.
    Type: Application
    Filed: September 6, 2012
    Publication date: February 7, 2013
    Inventors: Scott Thomas Allen, Qingchun Zhang
  • Publication number: 20130009238
    Abstract: This invention discloses a semiconductor power device that includes an active cell area having a plurality of power transistor cells. Each of said power transistor cells has a planar Schottky diode that includes a Schottky junction barrier metal covering areas above gaps between separated body regions between two adjacent power transistor cells. The separated body regions further provide a function of adjusting a leakage current of said Schottky diode in each of said power transistor cells. Each of the planar Schottky diodes further includes a Shannon implant region disposed in a gap between the separated body regions of two adjacent power transistor cells for further adjusting a leakage current of said Schottky diode. Each of the power transistor cells further includes heavy body doped regions in the separated body regions next to source regions surrounding said Schottky diode forming a junction barrier Schottky (JBS) pocket region.
    Type: Application
    Filed: January 12, 2012
    Publication date: January 10, 2013
    Inventors: Anup Bhalla, Xiaobin Wang, Moses Ho
  • Publication number: 20120326261
    Abstract: A semiconductor structure and a manufacturing method for the same are provided. The semiconductor structure includes a well region, a dielectric structure, a first doped layer, a second doped layer and a first doped region. The dielectric structure is on the well region. The dielectric structure has a first dielectric sidewall and a second dielectric sidewall opposite to each other. The dielectric structure includes a first dielectric portion and a second dielectric portion, between the first dielectric sidewall and the second dielectric sidewall. The first doped layer is on the well region between the first dielectric portion and the second dielectric portion. The second doped layer is on the first doped layer. The first doped region is in the well region on the first dielectric sidewall.
    Type: Application
    Filed: June 22, 2011
    Publication date: December 27, 2012
    Applicant: MACRONIX INTERNATIONAL CO., LTD.
    Inventors: Wing-Chor Chan, Chung-Yu Hung, Chien-Wen Chu
  • Patent number: 8324705
    Abstract: An integrated circuit structure includes a semiconductor substrate; a first well region of a first conductivity type over the semiconductor substrate; a second well region of a second conductivity type opposite the first conductivity type encircling the first well region; and a metal-containing layer over and adjoining the first well region and extending over at least an inner portion of the second well region. The metal-containing layer and the first well region form a Schottky barrier. The integrated circuit structure further includes an isolation region encircling the metal-containing layer; and a third well region of the second conductivity type encircling at least a central portion of the first well region. The third well region has a higher impurity concentration than the second well region, and includes a top surface adjoining the metal-containing layer, and a bottom surface higher than bottom surfaces of the first and the second well regions.
    Type: Grant
    Filed: May 27, 2008
    Date of Patent: December 4, 2012
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Chien-Shao Tang, Dah-Chuen Ho, Yu-Chang Jong, Zhe-Yi Wang, Yuh-Hwa Chang, Yogendra Yadav
  • Publication number: 20120302051
    Abstract: A silicon oxide film is formed on an epitaxial layer by dry thermal oxidation, an ohmic electrode is formed on a back surface of a SiC substrate, an ohmic junction is formed between the ohmic electrode and the back surface of the SiC substrate by annealing the SiC substrate, the silicon oxide film is removed, and a Schottky electrode is formed on the epitaxial layer. Then, a sintering treatment is performed to form a Schottky junction between the Schottky electrode and the epitaxial layer.
    Type: Application
    Filed: January 23, 2012
    Publication date: November 29, 2012
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Yoshinori MATSUNO, Yoichiro Tarui
  • Patent number: 8319308
    Abstract: The present invention provides a semiconductor device including: a base substrate; a first semiconductor layer disposed on the base substrate; first ohmic electrodes disposed on a central region of the first semiconductor layer; a second ohmic electrode having a ring shape surrounding the first ohmic electrodes, on edge regions of the first semiconductor layer; a second semiconductor layer interposed between the first ohmic electrodes and the first semiconductor layer; and a Schottky electrode part which covers the first ohmic electrodes on the central regions, and is spaced apart from the second ohmic electrode.
    Type: Grant
    Filed: January 7, 2010
    Date of Patent: November 27, 2012
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Woo Chul Jeon, Jung Hee Lee, Young Hwan Park, Ki Yeol Park
  • Publication number: 20120292732
    Abstract: A diode (200) is disclosed having improved efficiency, smaller form factor, and reduced reverse biased leakage current. Schottky diodes (212) are formed on the sidewalls (210) of a mesa region (206). The mesa region (206) is a cathode of the Schottky diode (212). The current path through the mesa region (206) has a lateral and a vertical current path. The diode (200) further comprises a MOS structure (214), p-type regions (220), MOS structures (230), and p-type regions (232). MOS structure (214) with the p-type regions (220) pinch-off the lateral current path under reverse bias conditions. P-type regions (220), MOS structures (230), and p-type regions (232) each pinch-off the vertical current path under reverse bias conditions. MOS structure (214) and MOS structures (230) reduce resistance of the lateral and vertical current path under forward bias conditions. The mesa region (206) can have a uniform or non-uniform doping concentration.
    Type: Application
    Filed: May 17, 2011
    Publication date: November 22, 2012
    Inventors: Gordon M. Grivna, Jefferson W. Hall, Mohammed Tanvir Quddus
  • Publication number: 20120292733
    Abstract: The present invention relates to the field of microelectronic technology. It discloses a mixed Schottky/P-N junction diode and a method of making the same. The mixed Schottky/P-N junction diode comprises a semiconductor substrate having a bulk region and a doped region, and a conductive layer on the semiconductor substrate. The doped region has opposite doping from that of the bulk region. A P-N junction is formed between the bulk region and the doped region, a Schottky junction is formed between the conductive layer and the semiconductor substrate, and an ohmic contact is formed between the conductive layer and the doped region. The mixed Schottky/P-N junction diode of the present invention has high operating current, fast switching speed, small leakage current, high breakdown voltage, ease of fabrication and other advantages.
    Type: Application
    Filed: January 4, 2011
    Publication date: November 22, 2012
    Applicant: FUDAN UNIVERSITY
    Inventors: Dongping Wu, Shi-Li Zhang, Yinghua Pu
  • Publication number: 20120280742
    Abstract: A coplanar waveguide (CPW) based subharmonic mixer working at 670 GHz using GaAs Schottky diodes. One example of the mixer has a LO input, an RF input and an IF output. Another possible mixer has a LO input, and IF input and an RF output. Each input or output is connected to a coplanar waveguide with a matching network. A pair of antiparallel diodes provides a signal at twice the LO frequency, which is then mixed with a second signal to provide signals having sum and difference frequencies. The output signal of interest is received after passing through a bandpass filter tuned to the frequency range of interest.
    Type: Application
    Filed: May 2, 2012
    Publication date: November 8, 2012
    Applicant: California Institute of Technology
    Inventors: Goutam Chattopadhyay, Erich T. Schlecht, Choonsup Lee, Robert H. Lin, John J. Gill, Seth Sin, Imran Mehdi
  • Publication number: 20120256192
    Abstract: An electronic device includes a drift region, a Schottky contact on a surface of the drift region, and an edge termination structure in the drift region adjacent the Schottky contact. The edge termination structure includes a recessed region that is recessed from the surface of the drift region by a distance d that may be about 0.5 microns.
    Type: Application
    Filed: April 5, 2011
    Publication date: October 11, 2012
    Inventors: Qingchun Zhang, Jason Henning
  • Publication number: 20120241897
    Abstract: A semiconductor system is described, which includes a trench junction barrier Schottky diode having an integrated p-n type diode as a clamping element, which is suitable for use in motor vehicle generator system, in particular as a Zener diode having a breakdown voltage of approximately 20V. In this case, the TJBS is a combination of a Schottky diode and a p-n type diode. Where the breakdown voltages are concerned, the breakdown voltage of the p-n type diode is lower than the breakdown voltage of Schottky diode. The semiconductor system may therefore be operated using high currents at breakdown.
    Type: Application
    Filed: June 9, 2010
    Publication date: September 27, 2012
    Inventors: Ning Qu, Alfred Goerlach
  • Publication number: 20120211859
    Abstract: A Schottky diode including a semiconductor region, a first terminal comprising a metal or a metal silicide or being metallic, and a second terminal comprising at least a portion of the semiconductor region. The diode further includes an at least partly conductive material or a material capable of holding a charge in close proximity to, or in contact with, or surrounding one of the first and second terminals, a field insulator located at least partly in the semiconductor region, a dielectric region located over the semiconductor region between the field insulator and the one of the first and second terminals for isolating the conductive or charge-holding material from the semiconductor region, and wherein the dielectric region comprises insulating regions of different thicknesses.
    Type: Application
    Filed: February 18, 2011
    Publication date: August 23, 2012
    Inventors: Paul R. Stribley, Suba Chithambaram Subramaniam
  • Publication number: 20120205772
    Abstract: A trench Schottky diode and a manufacturing method thereof are provided. A plurality of trenches are formed in Asemiconductor substrate. A plurality of doped regions are formed in the semiconductor substrate and under some of the trenches. A gate oxide layer is formed on a surface of the semiconductor substrate and the surfaces of the trenches. A polysilicon structure is formed on the gate oxide layer. Then, the polysilicon structure is etched, so that the gate oxide layer within the trenches is covered by the polysilicon structure. Then, a mask layer is formed to cover the polysilicon structure within a part of the trenches and a part of the gate oxide layer, and the semiconductor substrate uncovered by the mask layer is exposed. Afterwards, a metal sputtering layer is formed to cover a part of the surface of the semiconductor substrate.
    Type: Application
    Filed: February 15, 2012
    Publication date: August 16, 2012
    Inventor: TZU-HSIUNG CHEN
  • Publication number: 20120199937
    Abstract: An integrated circuit including a Schottky diode, and a method of making the same. The diode includes an active region bordered by an isolation region in a semiconductor substrate of the integrated circuits, a first electrode having a metal contact provided on a surface of the active region, and a second electrode having a silicide contact also provided on the surface of the active region.
    Type: Application
    Filed: October 21, 2010
    Publication date: August 9, 2012
    Inventors: Georgios Vellianitis, Gilberto Curatola, Kyriaki Fotopoulou, Nader Akil
  • Patent number: 8237239
    Abstract: A Schottky diode device is provided, including a p-type semiconductor structure. An n drift region is disposed over the p-type semiconductor structure, wherein the n drift region comprises first and second n-type doping regions having different n-type doping concentrations, and the second n-type doping region is formed with a dopant concentration greater than that in the first n-type doping region. A plurality of isolation structures is disposed in the second n-type doping region of the n drift region, defining an anode region and a cathode region. A third n-type doping region is disposed in the second n-type doping region exposed by the cathode region. An anode electrode is disposed over the first n-type doping region in the anode region. A cathode electrode is disposed over the third n-type doping region in the cathode region.
    Type: Grant
    Filed: October 28, 2009
    Date of Patent: August 7, 2012
    Assignee: Vanguard International Semiconductor Corporation
    Inventors: Huang-Lang Pai, Hung-Shern Tsai
  • Publication number: 20120193747
    Abstract: Disclosed are embodiments of a Schottky barrier diode. This diode can be formed in a semiconductor substrate having a doped region with a first conductivity type. A trench isolation structure can laterally surround a section of the doped region at the top surface of the substrate. A semiconductor layer can be positioned on the top surface of the substrate. This semiconductor layer can have a Schottky barrier portion over the defined section of the doped region and a guardring portion over the trench isolation structure laterally surrounding the Schottky barrier portion. The Schottky barrier portion can have the first conductivity type and the guarding portion can have a second conductivity type different from the first conductivity type. A metal silicide layer can overlie the semiconductor layer. Also disclosed are embodiments of a method of forming this Schottky barrier diode and of a design structure for the Schottky barrier diode.
    Type: Application
    Filed: February 2, 2011
    Publication date: August 2, 2012
    Applicant: International Business Machines Corporation
    Inventors: Robert M. Rassel, Mark E. Stidham
  • Publication number: 20120149183
    Abstract: A switching element that includes a first semiconductor layer, the first semiconductor layer having a first portion and a second portion; a second semiconductor layer, the second semiconductor layer having a first portion and a second portion; an insulating layer disposed between the first semiconductor layer and the second semiconductor layer; a first metal contact in contact with the first portion of the first semiconductor layer forming a first junction and in contact with the first portion of the second semiconductor layer forming a second junction; a second metal contact in contact with the second portion of the first semiconductor layer forming a third junction and in contact with the second portion of the second semiconductor layer forming a fourth junction, wherein the first junction and the fourth junction are Schottky contacts, and the second junction and the third junction are ohmic contacts.
    Type: Application
    Filed: February 20, 2012
    Publication date: June 14, 2012
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Young Pil Kim, Nurul Amin, Dadi Setiadi, Venugopalan Vaithyanathan, Wei Tian, Insik Jin
  • Publication number: 20120133016
    Abstract: A schottky diode includes a drift region of a first conductivity type and a lightly doped silicon region of the first conductivity type in the drift region. A conductor layer is over and in contact with the lightly doped silicon region to form a schottky contact with the lightly doped silicon region. A highly doped silicon region of the first conductivity type is in the drift region and is laterally spaced from the lightly doped silicon region such that upon biasing the schottky diode in a conducting state, a current flows laterally between the lightly doped silicon region and the highly doped silicon region through the drift region. A plurality of trenches extend into the drift region perpendicular to the current flow. Each trench has a dielectric layer lining at least a portion of the trench sidewalls and at least one conductive electrode.
    Type: Application
    Filed: February 3, 2012
    Publication date: May 31, 2012
    Applicant: Fairchild Semiconductor Corporation
    Inventor: Christopher Boguslaw Kocon
  • Publication number: 20120129328
    Abstract: A semiconductor device formed on a semiconductor substrate may include a component formed in a contact trench located in an active cell region. The component may comprise a barrier metal deposited on a bottom and portions of sidewalls of the contact trench and a tungsten plug deposited in a remaining portion of the contact trench. The barrier metal may comprise first and second metal layers. The first metal layer may be proximate to the sidewall and the bottom of the contact trench. The first metal layer may include a nitride. The second metal layer may be between the first metal layer and the tungsten plug and between the tungsten plug and the sidewall. The second metal layer covers portions of the sidewalls of not covered by the first metal layer.
    Type: Application
    Filed: January 30, 2012
    Publication date: May 24, 2012
    Applicant: ALPHA & OMEGA SEMICONDUCTOR, INC.
    Inventors: Hong Chang, John Chen, Limin Weng, Wenjun Li
  • Patent number: 8183660
    Abstract: A semiconductor component is proposed which has a semiconductor body having a first semiconductor zone of the first conduction type, at least one first rectifying junction with respect to the first semiconductor zone, at least one second rectifying junction with respect to the first semiconductor zone, wherein the three rectifying junctions each have a barrier height of different magnitude.
    Type: Grant
    Filed: February 26, 2008
    Date of Patent: May 22, 2012
    Assignee: Infineon Technologies AG
    Inventors: Michael Rueb, Roland Rupp, Michael Treu
  • Publication number: 20120122307
    Abstract: A method of manufacturing a semiconductor device is disclosed. The method includes forming a first trench and a second trench in an n-type substrate surface, the first trenches being spaced apart from each other, the second trench surrounding the first trenches, the second trench being wider than the first trench. The method also includes forming a gate oxide film on the inner surfaces of the first and second trenches, and depositing an electrically conductive material to the thickness a half or more as large as the first trench width. The method further includes removing the electrically conductive material using the gate oxide film as a stopper layer, forming an insulator film thicker than the gate oxide film, and polishing the insulator film by CMP for exposing the n-type substrate and the electrically conductive material in the first trench.
    Type: Application
    Filed: November 10, 2011
    Publication date: May 17, 2012
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventor: Tomonori Mizushima
  • Publication number: 20120115319
    Abstract: The present disclosure relates to forming multi-layered contact pads for a semiconductor device, wherein the various layers of the contact pad are formed using one or more thin-film deposition processes, such as an evaporation process. Each contact pad includes an adhesion layer, which is formed over the device structure for the semiconductor device; a titanium nitride (TiN) barrier layer, which is formed over the adhesion layer; and an overlay layer, which is formed over the barrier layer. At least the titanium nitride (TiN) barrier layer is formed using an evaporation process.
    Type: Application
    Filed: November 10, 2010
    Publication date: May 10, 2012
    Applicant: CREE, INC.
    Inventors: Van Mieczkowski, Zoltan Ring, Jason Gurganus, Helmut Hagleitner
  • Publication number: 20120104537
    Abstract: A semiconductor device and a method for forming a semiconductor device are provided. The semiconductor device includes a semiconductor body with a first semiconductor region and a second semiconductor region spaced apart from each other. A first metallization is in contact with the first semiconductor region. A second metallization is in contact with the second semiconductor region. An insulating region extends between the first semiconductor region and the second semiconductor region. A semi-insulating region having a resistivity of about 103 Ohm cm to about 1014 Ohm cm is arranged on the insulating region and forms a resistor between the first metallization and the second metallization.
    Type: Application
    Filed: November 3, 2010
    Publication date: May 3, 2012
    Applicant: INFINEON TECHNOLOGIES AG
    Inventors: Gerhard Schmidt, Daniel Schloegl
  • Patent number: 8168466
    Abstract: In one embodiment, a Schottky diode is formed on a semiconductor substrate with other semiconductor devices and is also formed with a high breakdown voltage and a low forward resistance.
    Type: Grant
    Filed: June 1, 2007
    Date of Patent: May 1, 2012
    Assignee: Semiconductor Components Industries, LLC
    Inventors: Mohammed Tanvir Quddus, Shanghui L. Tu, Antonin Rozsypal, Zia Hossain
  • Patent number: 8169047
    Abstract: The present invention aims to enhance the reliability of a semiconductor device equipped with a Schottky barrier diode within the same chip, and its manufacturing technology. The semiconductor device includes an n-type n-well region formed over a p-type semiconductor substrate, an n-type cathode region formed in part thereof and higher in impurity concentration than the n-well region, a p-type guard ring region formed so as to surround the n-type cathode region, an anode conductor film formed so as to integrally cover the n-type cathode region and the p-type guard ring region and to be electrically coupled thereto, n-type cathode conduction regions formed outside the p-type guard ring region with each separation portion left therebetween, and a cathode conductor film formed so as to cover the n-type cathode conduction regions and to be electrically coupled thereto. The anode conductor film and the n-type cathode region are Schottky-coupled to each other.
    Type: Grant
    Filed: September 5, 2008
    Date of Patent: May 1, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Kunihiko Kato, Hideki Yasuoka, Masatoshi Taya, Masami Koketsu
  • Publication number: 20120098082
    Abstract: A semiconductor rectifier includes a semiconductor substrate having a first type of conductivity. A first layer, which is formed on the substrate, has the first type of conductivity and is more lightly doped than the substrate. A second layer having a second type of conductivity is formed on the substrate and a metal layer is disposed over the second layer. The second layer is lightly doped so that a Schottky contact is formed between the metal layer and the second layer. A first electrode is formed over the metal layer and a second electrode is formed on a backside of the substrate.
    Type: Application
    Filed: August 31, 2011
    Publication date: April 26, 2012
    Applicant: VISHAY GENERAL SEMICONDUCTOR LLC
    Inventors: Chih-Wei HSU, Florin UDREA, Yih-Yin LIN
  • Patent number: 8143655
    Abstract: A fabrication process for a trench Schottky diode with differential oxide thickness within the trenches includes forming a first nitride layer on a substrate surface and subsequently forming a plurality of trenches in the substrate including, possibly, a termination trench. Following a sacrificial oxide layer formation and removal, sidewall and bottom surfaces of the trenches are oxidized. A second nitride layer is then applied to the substrate and etched such that the second nitride layer covers the oxide layer on the trench sidewalls but exposes the oxide layer on the trench bottom surfaces. The trench bottom surfaces are then re-oxidized and the remaining second nitride layer then removed from the sidewalls, resulting in an oxide layer of varying thickness being formed on the sidewall and bottom surfaces of each trench. The trenches are then filled with a P type polysilicon, the first nitride layer removed, and a Schottky barrier metal applied to the substrate surface.
    Type: Grant
    Filed: October 11, 2007
    Date of Patent: March 27, 2012
    Assignee: International Rectifier Corporation
    Inventor: Davide Chiola
  • Patent number: 8138073
    Abstract: A method for forming a metal-semiconductor Schottky contact in a well region is provided. The method includes forming a first insulating layer overlying a shallow trench isolation in the well region; and removing a portion of the first insulating layer such that only the well region and a portion of the shallow trench isolation is covered by a remaining portion of the first insulating layer. The method further includes forming a second insulating layer overlying the remaining portion of the first insulating layer and using a contact mask, forming a contact opening in the second insulating layer and the remaining portion of the first insulating layer to expose a portion of the well region. The method further includes forming the metal-semiconductor Schottky contact in the exposed portion of the well region by forming a metal layer in the contact opening and annealing the metal layer.
    Type: Grant
    Filed: April 23, 2010
    Date of Patent: March 20, 2012
    Assignee: Freescale Semiconductor, Inc.
    Inventor: Vishal P. Trivedi
  • Publication number: 20120061727
    Abstract: Gallium nitride (GaN) based semiconductor devices and methods of manufacturing the same. The GaN-based semiconductor device may include a heterostructure field effect transistor (HFET) or a Schottky diode, arranged on a heat dissipation substrate. The HFET device may include a GaN-based multi-layer having a recess region; a gate arranged in the recess region; and a source and a drain that are arranged on portions of the GaN-based multi-layer at two opposite sides of the gate (or the recess region). The gate, the source, and the drain may be attached to the heat dissipation substrate. The recess region may have a double recess structure. While such a GaN-based semiconductor device is being manufactured, a wafer bonding process and a laser lift-off process may be used.
    Type: Application
    Filed: September 2, 2011
    Publication date: March 15, 2012
    Inventors: Jae-hoon LEE, Ki-se Kim
  • Publication number: 20120056294
    Abstract: The present invention discloses a Schottky diode. The Schottky diode comprises a cathode region, an anode region and a guard ring region. The anode region may comprise a metal Schottky contact. The guard ring region may comprise an outer guard ring and a plurality of inner guard stripes inside the outer guard ring. And wherein the inner guard stripe has a shallower junction depth than the outer guard ring.
    Type: Application
    Filed: September 7, 2011
    Publication date: March 8, 2012
    Inventor: Ji-Hyoung Yoo
  • Publication number: 20120056198
    Abstract: A semiconductor device according to an embodiment includes a semiconductor substrate of a first conductivity type, a first semiconductor layer of the first conductivity type, a first semiconductor region of a second conductivity type, a second semiconductor region of the second conductivity type, a first electrode and a second electrode. The first semiconductor region is formed on at least a part of the first semiconductor layer formed on the semiconductor substrate. The second semiconductor region is formed on another part of the first semiconductor layer to reach an inside of the first semiconductor layer and having an impurity concentration higher than that of the first semiconductor region. The first electrode is formed on the second semiconductor region and a third semiconductor regions formed in a part of the first semiconductor region. The second electrode is formed to be in contact with a rear surface of the semiconductor substrate.
    Type: Application
    Filed: March 2, 2011
    Publication date: March 8, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Chiharu OTA, Hiroshi Kono, Kazuto Takao, Takashi Shinohe
  • Patent number: 8129814
    Abstract: An integrated circuit includes a Schottky diode having a cathode defined by an n-type semiconductor region, an anode defined by a cobalt silicide region, and a p-type region laterally annularly encircling the cobalt silicide region. The resulting p-n junction forms a depletion region under the Schottky junction that reduces leakage current through the Schottky diodes in reverse bias operation. An n+-type contact region is laterally separated by the p-type region from the first silicide region and a second cobalt silicide region is formed in the n-type contact region. The silicided regions are defined by openings in a silicon blocking dielectric layer. Dielectric material is left over the p-type region. The p-type region may be formed simultaneously with source/drain regions of a PMOS transistor.
    Type: Grant
    Filed: April 12, 2011
    Date of Patent: March 6, 2012
    Assignee: Texas Instruments Incorporated
    Inventors: Sameer Prakash Pendharkar, Eugen Pompiliu Mindricelu
  • Publication number: 20120018837
    Abstract: A Schottky barrier diode comprises a first-type substrate, a second-type well isolation region on the first-type substrate, and a first-type well region on the second-type well isolation region. With embodiments herein a feature referred to as a perimeter capacitance well junction ring is on the second-type well isolation region. A second-type well region is on the second-type well isolation region. The perimeter capacitance well junction ring is positioned between and separates the first-type well region and the second-type well region. A second-type contact region is on the second-type well region, and a first-type contact region contacts the inner portion of the first-type well region. The inner portion of the first-type well region is positioned within the center of the first-type contact region. Additionally, a first ohmic metallic layer is on the first-type contact region and a second ohmic metallic layer is on the first-type well region.
    Type: Application
    Filed: July 21, 2010
    Publication date: January 26, 2012
    Applicant: International Business Machines Coporation
    Inventors: Frederick G. Anderson, Jenifer E. Lary, Robert M. Rassel, Mark E. Stidham
  • Publication number: 20120012968
    Abstract: A device according to the invention comprises a Schottky barrier formed by a metal-semiconductor junction between a semiconductor nanowire (1) and a metal contact (5). The metal contact (5) at least partly encloses a circumferential area of each nanowire (1) along the length thereof. The nanowire (2) comprises a lowly doped region that is part of the metal-semiconductor junction. This lowly doped region can be formed by a nanowire segment, by the entire nanowire or in a core-shell configuration with a highly doped nanowire core (3) and the lowly doped region comprised in a shell (4). The device can be fabricated using a method according to the invention, where two different growth modes are used, the first comprising axial growth from a substrate (2) giving a suitable template for formation of the metal-semiconductor junction and the second step comprising radial growth enabling control of the doping levels in the lowly doped region.
    Type: Application
    Filed: March 25, 2010
    Publication date: January 19, 2012
    Applicant: QuNana AB
    Inventor: Steven Konsek
  • Publication number: 20120007097
    Abstract: A Schottky diode comprising a merged guard ring and field plate defining a Schottky contact region is provided. A Schottky metal is formed over at least partially over the Schottky contact region and at least partially over the merged guard ring and field plate.
    Type: Application
    Filed: November 11, 2010
    Publication date: January 12, 2012
    Applicant: INTERSIL AMERICAS INC.
    Inventor: Francois Hebert
  • Publication number: 20120007206
    Abstract: This invention discloses bottom-anode Schottky (BAS) device supported on a semiconductor substrate having a bottom surface functioning as an anode electrode with an epitaxial layer has a same doped conductivity as said anode electrode overlying the anode electrode. The BAS device further includes an Schottky contact metal disposed in a plurality of trenches and covering a top surface of the semiconductor substrate between the trenches. The BAS device further includes a plurality of doped JBS regions disposed on sidewalls and below a bottom surface of the trenches doped with an opposite conductivity type from the anode electrode constituting a junction barrier Schottky (JBS) with the epitaxial layer disposed between the plurality of doped JBS regions. The BAS device further includes an ultra-shallow Shannon implant layer disposed immediate below the Schottky contact metal in the epitaxial layer between the plurality of doped JBS regions.
    Type: Application
    Filed: August 23, 2011
    Publication date: January 12, 2012
    Inventors: Anup Bhalla, Sik K. Lui, Yi Su
  • Publication number: 20110309371
    Abstract: A Schottky diode structure and a method for fabricating the same, which are based on the principle of charge compensation, wherein a P-type gallium nitride layer is added to a Schottky diode structure, and wherein the PN junction of the P-type gallium nitride layer and the N-type gallium nitride layer decreases the non-uniformity of the surface electric field distribution, whereby the breakdown voltage of the element is raised.
    Type: Application
    Filed: June 16, 2010
    Publication date: December 22, 2011
    Inventors: Shuo-Hung Hsu, Yi-Wei Lian, Yu-Syuan Lin
  • Publication number: 20110297954
    Abstract: [Problem to be Solved] Provided is a semiconductor device in which the trade-off between the pressure resistance and the on-state resistance is improved and the performance is improved.
    Type: Application
    Filed: November 26, 2009
    Publication date: December 8, 2011
    Inventors: Yasuhiro Okamoto, Hironobu Miyamoto, Yuji Ando, Tatsuo Nakayama, Takashi Inoue, Kazuki Ota, Kazuomi Endo
  • Publication number: 20110284876
    Abstract: A semiconductor device provided with a silicon carbide semiconductor substrate, and an ohmic metal layer joined to one surface of the silicon carbide semiconductor substrate in an ohmic contact and composed of a metal material whose silicide formation free energy and carbide formation free energy respectively take negative values. The ohmic metal layer is composed of, for example, a metal material such as molybdenum, titanium, chromium, manganese, zirconium, tantalum, or tungsten.
    Type: Application
    Filed: August 8, 2011
    Publication date: November 24, 2011
    Applicant: ROHM CO. LTD.
    Inventors: Yuji Okamura, Masashi Matsushita
  • Publication number: 20110278598
    Abstract: A monolithic semiconductor structure includes a stack of layers. The stack includes a substrate; a first layer made from a first semiconductor material; and a second layer made from a second semiconductor material. The first layer is situated between the substrate and the second layer and at least one of the first semiconductor material and the second semiconductor material contains a III-nitride material. The structure includes a power transistor, including a body formed in the stack of layers; a first power terminal at a side of the first layer facing the second layer; a second power terminal at least partly formed in the substrate; and a gate structure for controlling the propagation through the body of electric signals between the first power terminal and the second power terminal.
    Type: Application
    Filed: February 3, 2009
    Publication date: November 17, 2011
    Applicant: Freescale Semiconductor, Inc.
    Inventor: Philippe Renaud
  • Publication number: 20110263112
    Abstract: A method for forming a metal-semiconductor Schottky contact in a well region is provided. The method includes forming a first insulating layer overlying a shallow trench isolation in the well region; and removing a portion of the first insulating layer such that only the well region and a portion of the shallow trench isolation is covered by a remaining portion of the first insulating layer. The method further includes forming a second insulating layer overlying the remaining portion of the first insulating layer and using a contact mask, forming a contact opening in the second insulating layer and the remaining portion of the first insulating layer to expose a portion of the well region. The method further includes forming the metal-semiconductor Schottky contact in the exposed portion of the well region by forming a metal layer in the contact opening and annealing the metal layer.
    Type: Application
    Filed: April 23, 2010
    Publication date: October 27, 2011
    Inventor: VISHAL P. TRIVEDI
  • Publication number: 20110254118
    Abstract: A Schottky diode optimizes the on state resistance, the reverse leakage current, and the reverse breakdown voltage of the Schottky diode by forming an insulated control gate over a region that lies between the metal-silicon junction of the Schottky diode and the n+ cathode contact of the Schottky diode.
    Type: Application
    Filed: April 20, 2010
    Publication date: October 20, 2011
    Inventors: Zia Alan Shafi, Jeffrey A. Babcock
  • Patent number: 8039328
    Abstract: A process for forming a trench Schottky barrier device includes the forming of an oxide layer within the trenches in the surface of a silicon wafer, and then depositing a full continuous metal barrier layer over the full upper surface of the wafer including the trench interiors and the mesas between trenches with a barrier contact made to the mesas only. Palladium, titanium or any conventional barrier metal can be used.
    Type: Grant
    Filed: October 17, 2006
    Date of Patent: October 18, 2011
    Assignee: International Rectifier Corporation
    Inventors: Giovanni Richieri, Rossano Carta
  • Patent number: 8030155
    Abstract: A method of forming a rectifying diode. The method comprises providing a first semiconductor region of a first conductivity type and having a first dopant concentration and forming a second semiconductor region in the first semiconductor region. The second semiconductor region has the first conductivity type and having a second dopant concentration greater than the first dopant concentration. The method also comprises forming a conductive contact to the first semiconductor region and forming a conductive contact to the second semiconductor region. The rectifying diode comprises a current path, and the path comprises: (i) the conductive contact to the first semiconductor region; (ii) the first semiconductor region; (iii) the second semiconductor region; and (iv) the conductive contact to the second semiconductor region. The second semiconductor region does not extend to a layer buried relative to the first semiconductor region.
    Type: Grant
    Filed: May 12, 2008
    Date of Patent: October 4, 2011
    Assignee: Texas Instruments Incorporated
    Inventors: Vladimir F. Drobny, Derek W. Robinson