Wide Bandgap Emitter Patents (Class 438/317)
  • Patent number: 10263074
    Abstract: Transistors suitable for high voltage and high frequency operation are disclosed. A nanowire is disposed vertically or horizontally on a substrate. A longitudinal length of the nanowire is defined into a channel region of a first semiconductor material, a source region electrically coupled with a first end of the channel region, a drain region electrically coupled with a second end of the channel region, and an extrinsic drain region disposed between the channel region and drain region. The extrinsic drain region has a wider bandgap than that of the first semiconductor. A gate stack including a gate conductor and a gate insulator coaxially wraps completely around the channel region, drain and source contacts similarly coaxially wrap completely around the drain and source regions.
    Type: Grant
    Filed: May 25, 2017
    Date of Patent: April 16, 2019
    Assignee: Intel Corporation
    Inventors: Han Wui Then, Robert Chau, Benjamin Chu-Kung, Gilbert Dewey, Jack Kavalieros, Matthew Metz, Niloy Mukherjee, Ravi Pillarisetty, Marko Radosavljevic
  • Patent number: 8981430
    Abstract: Embodiments of the present invention provide a bipolar transistor with low resistance base contact and method of manufacturing the same. The bipolar transistor includes an emitter, a collector, and an intrinsic base between the emitter and the collector. The intrinsic base extends laterally to an extrinsic base. The extrinsic base further includes a first semiconductor material with a first bandgap and a second semiconductor material with a second bandgap that is smaller than the first bandgap.
    Type: Grant
    Filed: December 11, 2012
    Date of Patent: March 17, 2015
    Assignee: International Business Machines Corporation
    Inventors: Francois Pagette, Kathryn T. Schonenberg
  • Publication number: 20150014704
    Abstract: A bipolar transistor includes a semiconductor structure including an emitter area, a base area and a collector area. The emitter area is electrically connected to an emitter contact of the bipolar transistor. Further, the emitter area has a first conductivity type. The base area is electrically connected to a base contact of the bipolar transistor. Further, the base area has at least mainly a second conductivity type. The collector area is electrically connected to a collector contact of the bipolar transistor and has at least mainly the first conductivity type. Further, the collector area includes a plurality of enclosed sub areas having the second conductivity type or the base area includes a plurality of enclosed sub areas having the first conductivity type.
    Type: Application
    Filed: July 11, 2013
    Publication date: January 15, 2015
    Inventors: Jens Konrath, Hans-Joachim Schulze
  • Patent number: 8927382
    Abstract: A method of manufacturing a photo-semiconductor device that has a photoconductive semiconductor film provided with electrodes and formed on a second substrate, the semiconductor film being formed by epitaxial growth on a first semiconductor substrate different from the second substrate, the second substrate being also provided with electrodes, and the electrodes of the second substrate and the electrodes of the photoconductive semiconductor film being held in contact with each other.
    Type: Grant
    Filed: January 3, 2012
    Date of Patent: January 6, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventor: Toshihiko Ouchi
  • Patent number: 8735256
    Abstract: A process, machine, manufacture, composition of matter, and improvement thereof, and method of making and method of using the same, as well as necessary intermediates, generally relating to the field of semiconductor devices, the structure of transistors, and the structure of compound semiconductor heterojunction bipolar transistors.
    Type: Grant
    Filed: February 6, 2012
    Date of Patent: May 27, 2014
    Assignee: Vega Wave Systems, Inc.
    Inventor: Alan Sugg
  • Patent number: 8653627
    Abstract: A semiconductor crystal having a recombination-inhibiting semiconductor layer of a second conductive type that is disposed in the vicinity of the surface between a base contact region and emitter regions and that separates the semiconductor surface having a large number of surface states from the portion that primarily conducts the positive hole electric current and the electron current. Recombination is inhibited, and the current amplification factor is thereby improved and the ON voltage reduced.
    Type: Grant
    Filed: May 6, 2013
    Date of Patent: February 18, 2014
    Assignee: Honda Motor Co., Ltd.
    Inventor: Ken-ichi Nonaka
  • Patent number: 8574994
    Abstract: A heterojunction bipolar transistor is formed with an emitter electrode that comprises an emitter epitaxy underlying an emitter metal cap and that has horizontal dimensions that are substantially equal to the emitter metal cap.
    Type: Grant
    Filed: October 22, 2010
    Date of Patent: November 5, 2013
    Assignee: HRL Laboratories, LLC
    Inventor: Charles H. Fields
  • Patent number: 8557670
    Abstract: A lateral heterojunction bipolar transistor is formed on a semiconductor-on-insulator substrate including a top semiconductor portion of a first semiconductor material having a first band gap and a doping of a first conductivity type. A stack of an extrinsic base and a base cap is formed such that the stack straddles over the top semiconductor portion. A dielectric spacer is formed around the stack. Ion implantation of dopants of a second conductivity type is performed to dope regions of the top semiconductor portion that are not masked by the stack and the dielectric spacer, thereby forming an emitter region and a collector region. A second semiconductor material having a second band gap greater than the first band gap and having a doping of the second conductivity type is selectively deposited on the emitter region and the collector region to form an emitter contact region and a collector contact region, respectively.
    Type: Grant
    Filed: September 6, 2012
    Date of Patent: October 15, 2013
    Assignee: International Business Machines Corporation
    Inventors: Jin Cai, Kevin K. Chan, Christopher P. D'Emic, Tak H. Ning, Dae-Gyu Park
  • Patent number: 8460994
    Abstract: A semiconductor crystal includes a recombination-inhibiting semiconductor layer (17) of a second conductive type that is disposed in the vicinity of the surface between a base contact region (16) and emitter regions (14) and that separates the semiconductor surface having a large number of surface states from the portion that primarily conducts the positive hole electric current and the electron current. Recombination is inhibited, and the current amplification factor is thereby improved and the ON voltage reduced.
    Type: Grant
    Filed: June 9, 2006
    Date of Patent: June 11, 2013
    Assignee: Honda Motor Co., Ltd.
    Inventor: Ken-ichi Nonaka
  • Patent number: 8450146
    Abstract: A method for manufacturing a transistor assembly includes the steps of: (a) forming a transistor; (b) polishing a base substrate; and (c) securing the transistor of which the base substrate is polished to a support substrate. The step (a) is a step of forming a first semiconductor layer and a second semiconductor layer on a principle surface of the base substrate. The step (b) is a step of polishing a surface of the base substrate opposite to the principle surface. The step (c) is a step of securing the transistor on the support substrate in the presence of a stress applied on the base substrate in such a direction that a warp of the base substrate is reduced. The base substrate is made of a material different from that of the first semiconductor layer and the second semiconductor layer, and a tensile stress is applied on the second semiconductor layer.
    Type: Grant
    Filed: August 19, 2011
    Date of Patent: May 28, 2013
    Assignee: Panasonic Corporation
    Inventors: Kenichiro Tanaka, Tetsuzo Ueda, Hisayoshi Matsuo, Masahiro Hikita
  • Patent number: 8110472
    Abstract: A semiconductor power device is formed on a semiconductor substrate. The semiconductor power device includes a plurality of transistor cells distributed over different areas having varying amount of ballasting resistances depending on a local thermal dissipation in each of the different areas. An exemplary embodiment has the transistor cells with a lower ballasting resistance formed near a peripheral area and the transistor cells having a higher ballasting resistance are formed near a bond pad area. Another exemplary embodiment comprises cells with a highest ballasting resistance formed in an area around a wire-bonding pad, the transistor cells having a lower resistance are formed underneath the wire-bonding pad connected to bonding wires for dissipating heat and the transistor cells having a lowest ballasting resistance are formed in an areas away from the bonding pad.
    Type: Grant
    Filed: August 23, 2011
    Date of Patent: February 7, 2012
    Assignee: Alpha and Omega Semiconductor Ltd
    Inventors: François Hébert, Anup Bhalla
  • Patent number: 8044485
    Abstract: A semiconductor device made of a group-III nitride semiconductor having excellent properties is provided. The semiconductor device has a horizontal diode structure of Schottky type or P-N junction type, or combined type thereof having a main conduction pathway in the horizontal direction in a conductive layer with unit anode portions and unit cathode electrodes being integrated adjacently to each other in the horizontal direction. The conductive layer is preferably formed by depositing a group-III nitride layer and generating a two-dimensional electron gas layer on the interface. Forming the conductive layer of the group-III nitride having high breakdown field allows the breakdown voltage to be kept high while the gap between electrodes is narrow, which achieves a semiconductor device having high output current per chip area.
    Type: Grant
    Filed: March 28, 2007
    Date of Patent: October 25, 2011
    Assignee: NGK Insulators, Ltd.
    Inventors: Makoto Miyoshi, Yoshitaka Kuraoka
  • Patent number: 7892943
    Abstract: A first dielectric plug is formed in a portion of a trench that extends into a substrate of a memory device so that an upper surface of the first dielectric plug is recessed below an upper surface of the substrate. The first dielectric plug has a layer of a first dielectric material and a layer of a second dielectric material formed on the layer of the first dielectric material. A second dielectric plug of a third dielectric material is formed on the upper surface of the first dielectric plug.
    Type: Grant
    Filed: December 21, 2007
    Date of Patent: February 22, 2011
    Assignee: Micron Technology, Inc.
    Inventor: Michael Violette
  • Patent number: 7888199
    Abstract: A semiconductor light-emitting transistor device, including: a bipolar pnp transistor structure having a p-type collector, an n-type base, and a p-type emitter; a first tunnel junction coupled with the collector, and a second tunnel junction coupled with the emitter; and a collector contact coupled with the first tunnel junction, an emitter contact coupled with the second tunnel junction, and a base contact coupled with the base; whereby, signals applied with respect to the collector, base, and emitter contacts causes light emission from the base by radiative recombination in the base.
    Type: Grant
    Filed: September 25, 2008
    Date of Patent: February 15, 2011
    Assignee: The Board of Trustees of the University of Illinois
    Inventors: Gabriel Walter, Nick Holonyak, Jr., Milton Feng, Richard Chan
  • Patent number: 7875523
    Abstract: A heterojunction bipolar transistor is formed with an emitter electrode that comprises an emitter epitaxy underlying an emitter metal cap and that has horizontal dimensions that are substantially equal to the emitter metal cap.
    Type: Grant
    Filed: June 16, 2005
    Date of Patent: January 25, 2011
    Assignee: HRL Laboratories, LLC
    Inventor: Charles H. Fields
  • Patent number: 7723198
    Abstract: An integrated semiconductor cascode circuit is provided that comprises an emitter layer, a first base area, a second base area, an intermediate area and a collector area. The first base area is arranged between the emitter layer and the intermediate area, and the second base area is arranged between the intermediate area and the collector area. A dielectric layer that is provided with a central opening is arranged between the first base area and the second base area. The invention also relates to a method for the production of said semiconductor cascode circuit.
    Type: Grant
    Filed: March 14, 2007
    Date of Patent: May 25, 2010
    Assignee: Atmel Automotive GmbH
    Inventor: Peter Brandl
  • Patent number: 7638820
    Abstract: Provided is a process for forming a contact for a compound semiconductor device without electrically shorting the device. In one embodiment, a highly doped compound semiconductor material is electrically connected to a compound semiconductor material of the, same conductivity type through an opening in a compound semiconductor material of the opposite conductivity type. Another embodiment discloses a transistor including multiple compound semiconductor layers where a highly doped compound semiconductor material is electrically connected to a compound semiconductor layer of the same conductivity type through an opening in a compound semiconductor layer of the opposite conductivity type. Embodiments further include metal contacts electrically connected to the highly doped compound semiconductor material. A substantially planar semiconductor device is disclosed. In embodiments, the compound semiconductor material may be silicon carbide.
    Type: Grant
    Filed: November 6, 2006
    Date of Patent: December 29, 2009
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Martin E. Kordesch, Howard D. Bartlow, Richard L. Woodin
  • Publication number: 20090283802
    Abstract: A heterojunction bipolar transistor (HBT) device and system having electrostatic discharge ruggedness, and methods for making the same, are disclosed. An HBT device having electrostatic discharge ruggedness may include one or more emitter fingers including an emitter layer, a transition layer formed over the emitter layer, and an emitter cap layer formed over the transition layer.
    Type: Application
    Filed: May 15, 2008
    Publication date: November 19, 2009
    Applicant: TRIQUINT SEMICONDUCTOR, INC.
    Inventors: Timothy Henderson, Jeremy Middleton, John Hitt
  • Patent number: 7482237
    Abstract: The temperature of a bipolar semiconductor element using a wide-gap semiconductor is raised using heating means, such as a heater, to obtain a power semiconductor device being large in controllable current and low in loss. The temperature is set at a temperature higher than the temperature at which the decrement of the steady loss of the wide-gap bipolar semiconductor element corresponding to the decrement of the built-in voltage lowering depending on the temperature rising of the wide-gap bipolar semiconductor element is larger than the increment of the steady loss corresponding to the increment of the ON resistance increasing depending on the temperature rising.
    Type: Grant
    Filed: April 19, 2006
    Date of Patent: January 27, 2009
    Assignee: The Kansai Electric Power Co, Inc.
    Inventor: Yoshitaka Sugawara
  • Publication number: 20080237643
    Abstract: A heterojunction bipolar transistor comprising a substrate; a collector on the substrate; a base layer on the collector; an emitter layer on the base layer; the emitter layer comprising an upper emitter layer and a lower emitter layer between the upper emitter layer and base; the collector, base and emitter layers being npn or pnp doped respectively; characterised in that the lower emitter layer has a larger bandgap than the base layer and is AlxIn1-xP or GaxAl1-xP, x being in the range 0+ to 1.
    Type: Application
    Filed: March 27, 2008
    Publication date: October 2, 2008
    Applicant: FITRONIC COMPOUND SEMICONDUCTORS LIMITED
    Inventors: Matthew Francis O'Keefe, Robert Grey, Michael Charles Clausen, Richard Alun Davies
  • Publication number: 20080230809
    Abstract: A sophisticated semiconductor device capable of being fabricated without introducing a high-precision exposure apparatus is obtained. This semiconductor device includes a conductive layer formed on a first conductivity type collector layer, a first conductivity type emitter electrode formed on the conductive layer and a protruding portion protruding from an outer side toward an inner side of the emitter electrode along an interface between the emitter electrode and the conductive layer. The conductive layer has a first conductivity type emitter diffusion layer in contact with the emitter electrode through the protruding portion and a second conductivity type base layer.
    Type: Application
    Filed: February 28, 2008
    Publication date: September 25, 2008
    Inventor: Yoshikazu Ibara
  • Publication number: 20080121938
    Abstract: In a nitride semiconductor based bipolar transistor, a contact layer formed so as to contact an emitter layer is composed of n-type InAlGaN quaternary mixed crystals, the emitter layer and the contact layer are selectively removed so that the barrier height with the emitter formed thereon is small, and the ohmic electrode contact resistance can be lowered on the InAlGaN quaternary mixed crystals, for example, so that a WSi emitter electrode becomes an eave. A base electrode is formed by a self-aligned process using the emitter electrode as a mask. By such a configuration, the distance between the emitter and the edge of the base electrode is sufficiently shortened, and the base resistance can be lowered. As a result, a bipolar transistor having favorable high-frequency characteristics can be realized.
    Type: Application
    Filed: June 20, 2007
    Publication date: May 29, 2008
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuo Morita, Tetsuzo Ueda
  • Publication number: 20070148890
    Abstract: A method for pseudomorphic growth and integration of a strain-compensated metastable and/or unstable compound base having incorporated oxygen and an electronic device incorporating the base is described. The strain-compensated base is doped by substitutional and/or interstitial placement of a strain-compensating atomic species. The electronic device may be, for example, a SiGe NPN HBT.
    Type: Application
    Filed: December 27, 2005
    Publication date: June 28, 2007
    Inventors: Darwin G. Enicks, John T. Chaffee, Damian A. Carver
  • Patent number: 7208387
    Abstract: A method for producing a compound semiconductor wafer used for production of HBT by vapor growth of a sub-collector layer, a collector layer, a base layer and an emitter layer in this turn on a compound semiconductor substrate using MOCVD method wherein the base layer is grown as a p-type compound semiconductor thin film layer containing at least one of Ga, Al and In as a Group III element and As as a Group V element under such growth conditions that the growth rate gives a growth determined by a Group V gas flow rate-feed.
    Type: Grant
    Filed: August 1, 2003
    Date of Patent: April 24, 2007
    Assignees: Sumitomo Chemical Company, Limited, Sumika Epi Solution Company, Ltd.
    Inventors: Hisashi Yamada, Noboru Fukuhara
  • Patent number: 7192838
    Abstract: Method of producing complementary SiGe bipolar transistors. In a method of producing complementary SiGe bipolar transistors, interface oxide layers (38, 58) for NPN and PNP emitters (44, 64), are separately formed and emitter polysilicon (40, 60) is separately patterned, allowing these layers to be optimized for the respective conductivity type.
    Type: Grant
    Filed: August 26, 2004
    Date of Patent: March 20, 2007
    Assignee: Texas Instruments Incorporated
    Inventors: Philipp Steinmann, Scott Balster, Badih El-Kareh, Thomas Scharnagl
  • Patent number: 7176098
    Abstract: A heterojunction bipolar transistor comprises a collector layer, a base layer formed on the collector layer and an emitter layer formed on the base layer. The emitter layer includes a first semiconductor layer covering the entire top surface of the base layer and a second semiconductor layer formed on a predetermined part of the first semiconductor layer. An inactivated region is formed, by ion implantation, in a region of the collector layer located below the base layer except for a part thereof corresponding to the second semiconductor layer. The edge of the inactivated region is located away from the edge of the second semiconductor layer, and a region of the first semiconductor layer between the edge of the inactivated region and the edge of the second semiconductor layer is depleted.
    Type: Grant
    Filed: February 23, 2005
    Date of Patent: February 13, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Keisuke Kojima, Toshiharu Tanbo, Keiichi Murayama
  • Patent number: 7119382
    Abstract: The present invention realizes a heterobipolar transistor using a SiGeC base layer in order to improve its electric characteristics. Specifically, the distribution of carbon and boron within the base layer is controlled so that the concentration of boron is higher than the concentration of carbon on the side bordering on the emitter layer, and upon the formation of the emitter layer, both boron and carbon are dispersed into a portion of the emitter layer that comes into contact with the base layer.
    Type: Grant
    Filed: April 15, 2003
    Date of Patent: October 10, 2006
    Assignee: Fujitsu Limited
    Inventors: Hidekazu Sato, Takae Sukegawa, Kousuke Suzuki
  • Patent number: 7118982
    Abstract: An emitter includes an electron source and a cathode. The cathode has an emissive surface. The emitter further includes a continuous anisotropic conductivity layer disposed between the electron source and the emissive surface of the cathode. The anisotropic conductivity layer has an anisotropic sheet resistivity profile and provides for substantially uniform emissions over the emissive surface of the emitter.
    Type: Grant
    Filed: September 7, 2004
    Date of Patent: October 10, 2006
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Alexander Govyadinov, Michael J. Regan
  • Patent number: 7091082
    Abstract: A method for enhancing operation of a bipolar light-emitting transistor includes the following steps: providing a bipolar light-emitting transistor having emitter, base, and collector regions; providing electrodes for coupling electrical signals with the emitter, base, and collector regions; and adapting the base region to promote carrier transport from the emitter region toward the collector region by providing, in the base region, several spaced apart quantum size regions of different thicknesses, with the thicknesses of the quantum size regions being graded from thickest near the collector to thinnest near the emitter.
    Type: Grant
    Filed: June 4, 2004
    Date of Patent: August 15, 2006
    Assignee: The Board of Trustees of the University of Illinois
    Inventors: Milton Feng, Nick Holonyak, Jr.
  • Patent number: 7030462
    Abstract: A Heterojunction Bipolar Transistor, HBT, (100) containing a collector layer (104), a base layer (105) and an emitter layer (106) is constructed such that the collector layer (104), the base layer (105) and the emitter layer (106) have different lattice constants of ac, ab and ae respectively, and a value of ab between values of ac and ae (in other words, the values of ac, ab and ae satisfy a relationship of ac>ab>ae or ac<ab<ae). According to the present invention, the HBT having a high reliability can be realized without altering the existing apparatus and steps for producing the HBT extensively.
    Type: Grant
    Filed: October 29, 2003
    Date of Patent: April 18, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Motoji Yagura
  • Patent number: 7005362
    Abstract: A method of fabricating a TFT includes a step of forming an impurity region for a source and a drain by simultaneously implanting and activating impurity ions. More particularly, the present invention includes the steps of forming a gate insulating layer and a gate on a predetermined and selected portion of an active layer, forming an excited region in the exposed portion of the active layer by implanting hydrogen ions to the active layer by using the gate as a mask, and forming an impurity region by implanting impurity ions heavily to the excited region which remains in an excited state.
    Type: Grant
    Filed: June 7, 2001
    Date of Patent: February 28, 2006
    Assignee: LG.Philips LCD Co., Ltd.
    Inventor: Joon-Young Yang
  • Patent number: 6953728
    Abstract: This semiconductor device manufacturing method comprises the steps of: forming a thick gate oxide film (thick oxide film) in a first region of a substrate, forming a thin gate oxide film (thin oxide layer) in a second region, and then, applying oxynitridation to these gate oxide films; forming gate electrodes to 1d on these gate oxide films; and implanting an ion that contains nitrogen or nitrogen atoms into at least one part of an interface between the hick gate oxide film (thick oxide film) and the substrate before or after the step of forming the gate electrodes, thereby forming a highly oxy-nitrided region. In this manner, in a semiconductor device in which there coexist a MISFET having a thin gate insulation film and a MISFET having a thick gate insulation film, hot carrier reliability of the MISFET having the thick gate insulation film is improved.
    Type: Grant
    Filed: February 11, 2004
    Date of Patent: October 11, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Eiichi Murakami, Akio Nishida, Kazunori Umeda, Kousuke Okuyama, Toshiaki Yamanaka, Jiro Yugami, Shinichiro Kimura
  • Patent number: 6924201
    Abstract: A heterojunction bipolar transistor of the present invention is produced from a wafer including a substrate and a collector layer of a first conductivity type, a base layer of a second conductivity type and an emitter layer of the first conductivity type sequentially laminated on the substrate in this order. First, the wafer is etched up to a preselected depth of the collector layer via a first photoresist, which is formed at a preselected position on the emitter layer, serving as a mask. Subsequently, the collector layer etched with at least the sidewalls of the base layer and collector layer, which are exposed by the first etching step, and a second photoresist covering part of the surface of the collector layer contiguous with the sidewalls serving as a mask.
    Type: Grant
    Filed: May 29, 2003
    Date of Patent: August 2, 2005
    Assignee: NEC Compound Semiconductor Devices, Ltd.
    Inventors: Masahiro Tanomura, Hidenori Shimawaki, Yosuke Miyoshi, Fumio Harima
  • Patent number: 6917061
    Abstract: A heterojunction bipolar transistor is provided that has a reduced turn-on voltage threshold. A base spacer layer is provided and alternately an emitter layer is provided that has a lowered energy gap. The lowered energy gap of the base spacer or the emitter spacer allow the heterojunction bipolar transistor to realize a lower turn-on voltage threshold. The thickness of the emitter layer if utilized is kept to a minimum to reduce the associated space charge recombination current in the heterojunction bipolar transistor.
    Type: Grant
    Filed: July 22, 2002
    Date of Patent: July 12, 2005
    Assignee: Microlink Devices, Inc.
    Inventors: Noren Pan, Byung-Kwon Han
  • Patent number: 6905929
    Abstract: Leakage of a single-poly EPROM cell is prevented by eliminating field oxide isolating the source, channel, and drain from the control gate n-well, and by replacing field oxide surrounding the cell with a heavily doped surface isolation region. The EPROM cell also utilizes a floating gate having an open-rectangular floating gate portion over the control gate region, and a narrow floating gate portion over the channel and intervening silicon substrate. The surface area of the open-rectangular floating gate portion ensures a high coupling ratio with the control gate region. The small width of the narrow floating gate portion prevents formation of a sizeable leakage path between the n-well and the source, channel, and drain. To conserve surface area, the EPROM cell also eliminates the p+ contact region and the PLDD region in the control gate well of the conventional EPROM design.
    Type: Grant
    Filed: October 28, 2002
    Date of Patent: June 14, 2005
    Assignee: National Semiconductor Corporation
    Inventors: Richard B. Merrill, Albert Bergemont, Min-hwa Chi
  • Patent number: 6894362
    Abstract: Disclosed is a manufacturing method to fabricate Heterojunction Bipolar Transistors (HBTs) that enables self-alignment of emitter and base metal contact layers with precise sub-micron spacing using a dielectric-assisted metal lift-off process. Such an HBT process relies on the formation of an “H-shaped” dielectric (i.e., Si3N4/SiO2) mask conformally deposited on top of the emitter contact metallization that is used to remove excess base metal through lift-off by a wet chemical HF-based etch. This HBT process also uses a thin selective etch-stop layer buried within the emitter layer to prevent wet chemical over-etching to the base and improves HBT reliability by forming a non-conducting, depleted ledge above the extrinsic base layer. The geometry of the self-aligned emitter and base metal contacts in the HBT insures conformal coverage of dielectric encapsulation films, preferably Si3N4 and/or SiO2, for reliable HBT emitter p-n junction passivation.
    Type: Grant
    Filed: March 28, 2003
    Date of Patent: May 17, 2005
    Inventor: Roger J. Malik
  • Patent number: 6873029
    Abstract: A heterojunction bipolar transistor with self-aligned features having a self-aligned dielectric sidewall spacer disposed between base contact and emitter contact, and self-aligned base mesa aligned relative to self-aligned base contact. The base contact is self-aligned relative to the self-aligned dielectric sidewall spacer providing a predetermined base-to-emitter spacing thereby. The emitter may be an n-type, InP material; the base can be a p-type InGaAs material, possibly carbon-doped. The fabrication method includes forming a emitter electrode on an emitter layer; using the emitter contact as a mask, anisotropically etching the emitter exposing the base layer; forming a self-aligned dielectric sidewall spacer upon the emitter and base; self-alignedly depositing a self-aligned base electrode; using the self-aligned base electrode as a mask, anisotropically etching the base layer to expose the subcollector; and depositing a collector electrode on the subcollector layer.
    Type: Grant
    Filed: February 10, 2003
    Date of Patent: March 29, 2005
    Assignee: Vitesse Semiconductor Corporation
    Inventors: Gang He, James Howard
  • Patent number: 6855948
    Abstract: A heterojunction bipolar transistor is presented, comprising a substrate having formed thereon a heterojunction bipolar transistor layer structure, and including an emitter layer. The emitter layer includes a strained, n-doped compound of indium arsenic and phosphorus. The transistor further comprises, between the substrate and emitter layer, a subcollector layer, a collector layer, a base layer, and an optional spacer layer. The emitter layer may include a graded portion. A contact layer is formed on the emitter layer to provide contacts for the device.
    Type: Grant
    Filed: December 18, 2002
    Date of Patent: February 15, 2005
    Assignee: HRL Laboratories, LLC
    Inventors: David Chow, Kenneth Elliott, Chanh Nguyen
  • Patent number: 6847063
    Abstract: In a semiconductor device acting as an HBT, an emitter/base laminate portion is provided on a Si epitaxially grown layer in the SiGeC-HBT. The emitter/base laminate portion includes a SiGeC spacer layer, a SiGeC core base layer containing the boron, a Si cap layer, and an emitter layer formed by introducing phosphorous into the Si cap layer. The C content of the SiGeC spacer layer is equal to or lower than that of the SiGeC core base layer.
    Type: Grant
    Filed: April 15, 2003
    Date of Patent: January 25, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Teruhito Ohnishi, Koichiro Yuki, Shigeki Sawada, Keiichiro Shimizu, Koichi Hasegawa, Tohru Saitoh, Paul A. Clifton
  • Patent number: 6847062
    Abstract: In a semiconductor device functioning as a SiGeC-HBT, an emitter/base stacked portion 20 is formed on a Si epitaxially grown layer 2. The emitter/base stacked portion 20 includes: a SiGeC spacer layer 21; a SiGeC core base layer 22 containing boron at a high concentration, a SiGe cap layer 23; a Si cap layer 24, and an emitter layer 25 formed by introducing phosphorus into the Si cap layer 24 and the SiGe cap layer 23.
    Type: Grant
    Filed: April 15, 2003
    Date of Patent: January 25, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Teruhito Ohnishi, Koichiro Yuki, Shigeki Sawada, Keiichiro Shimizu, Koichi Hasegawa, Tohru Saitoh
  • Patent number: 6818520
    Abstract: According to one exemplary embodiment, a heterojunction bipolar transistor comprises a base. The heterojunction bipolar transistor further comprises a first nitride spacer and a second nitride spacer situated on the base, where the first nitride spacer and the second nitride spacer are separated by a distance substantially equal to a critical dimension. For example, the first nitride spacer and the second nitride spacer may comprise LPCVD or RTCVD silicon nitride. According to this exemplary embodiment, the heterojunction bipolar transistor further comprises an emitter situated between said first nitride spacer and said second nitride spacer, where the emitter has a width substantially equal to the critical dimension. The emitter may, for example, comprise polycrystalline silicon. In another embodiment, a method that achieves the above-described heterojunction bipolar transistor is disclosed.
    Type: Grant
    Filed: February 10, 2003
    Date of Patent: November 16, 2004
    Assignee: Newport Fab, LLC dba Jazz Semiconductor
    Inventor: Klaus F. Schuegraf
  • Publication number: 20040224463
    Abstract: A method for forming a heterojunction bipolar transistor (HBT) includes forming an etch mask atop an emitter cap layer of the HBT to expose a portion of the emitter cap layer, and selectively etching the exposed portion of the emitter cap layer to (1) form a reentry feature and (2) to expose a portion of the emitter layer. The method further includes selectively etching the exposed portion of the emitter layer to expose a portion of the base layer, and forming a metal layer over the exposed portion of the base layer and the exposed portion of the emitter cap layer.
    Type: Application
    Filed: April 16, 2004
    Publication date: November 11, 2004
    Inventors: Scott A. McHugo, Gregory N. DeBrabander
  • Publication number: 20040214401
    Abstract: A passivation layer for a heterojunction bipolar transistor (HBT) is formed from a relatively high bandgap material that is lattice-matched to the HBT components it passivates. By selecting the passivation layer to have a higher bandgap than the HBT components, minority carriers are contained within the HBT by the passivation layer. At the same time, the lattice matching of the passivation layer ensures a robust bond that prevents the subsequent formation of dangling bonds at the exterior surfaces of the base and collector (and/or other passivated surfaces), thereby minimizing surface leakage currents.
    Type: Application
    Filed: April 23, 2003
    Publication date: October 28, 2004
    Applicant: TriQuint Semiconductor, Inc.
    Inventors: Martha R. Krueger, Andrew N. MacInnes
  • Patent number: 6806512
    Abstract: Bipolar junction transistor (BJT) devices, particularly heterojunction bipolar transistor (HBT) devices, and methods of making same are described. A combination of InPSb and &rgr;-type InAs is used to create extremely high speed bipolar devices which, due to reduced turn-on voltages, lend themselves to circuits having drastically reduced power dissipation. The described HBTs are fabricated on InAs or GaSb substrates, and include an InPSb emitter. The base includes In and As, in the form of InAs when on an InAs substrate, and as InAsSb when on a GaSb substrate. The collector may be the same as the base to form a single heterojunction bipolar transistor (SHBT) or may be the same as the emitter to form a double heterojunction bipolar transistor (DHBT). Heterojunctions preferably include a grading layer, which may be implemented by continuously changing the bulk material composition, or by forming a chirped superlattice of alternating materials.
    Type: Grant
    Filed: October 3, 2002
    Date of Patent: October 19, 2004
    Assignee: HRL Laboratories, LLC
    Inventors: Chanh Nguyen, Daniel P. Docter
  • Patent number: 6797580
    Abstract: According to one exemplary embodiment, a method for fabricating a bipolar transistor in a BiCMOS process comprises a step of forming an emitter window stack by sequentially depositing a base oxide layer and an antireflective coating layer on a top surface of a base, where the emitter window stack does not comprise a polysilicon layer. The method further comprises etching an emitter window opening in the emitter window stack. The method further comprises depositing an emitter layer in the emitter window opening and over the antireflective coating layer and etching the emitter layer to form an emitter. The method further comprises etching a first portion of the base oxide layer not covered by the emitter using a first etchant, thereby causing the first portion of the base oxide layer to have a thickness less than a thickness of a second portion of the base oxide layer covered by the emitter.
    Type: Grant
    Filed: February 21, 2003
    Date of Patent: September 28, 2004
    Assignee: Newport Fab, LLC
    Inventors: Kevin Q. Yin, Amol Kalburge, Kenneth M. Ring
  • Publication number: 20040169197
    Abstract: In the present invention, a semiconductor device is formed which includes an MIM capacitor located on the upper surface of a heterostructure from which the emitter, base and collector sections of a nearby HBT are defined. In this way the capacitor and HBT share a substantially common structure, with the base and emitter electrodes of the HBT fashioned from the same metal layers as the upper and lower capacitor plates, respectively. Furthermore, as the insulator region of the capacitor is formed prior to definition of the HBT structure, the dielectric material used can be deposited by means of a plasma enhanced process, without damaging the HBT structure.
    Type: Application
    Filed: March 4, 2004
    Publication date: September 2, 2004
    Inventors: Hiroshi Nakamura, Ting Cheong Ang, Kian Siong Ang, Subrata Halder, Geok Ing Ng
  • Patent number: 6784064
    Abstract: A method of making a heterojunction bipolar transistor comprises the steps of: forming a mask layer on a compound semiconductor film by using a photomask for forming an emitter; and forming the emitter by wet-etching the compound semiconductor film by using the mask layer. The photomask has a pattern thereon for forming the emitter. The pattern is defined by a first area R associated with the shape of the emitter to be formed, and a plurality of second areas T1 to T4. Each of the second areas T1 to T4 includes first and second sides S1 and S2 meeting each other to form an acute angle therebetween, and a third side S3 in contact with the first area R. In each of the second areas T1 to T4, one side S3 of the two sides meeting each other to form a right angle therebetween is in contact with one side of the area R, whereas the other side S1 is connected to another side of the first area R to form a line segment.
    Type: Grant
    Filed: December 27, 2001
    Date of Patent: August 31, 2004
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Seiji Yaegashi, Kenji Kotani, Masaki Yanagisawa, Hiroshi Yano
  • Patent number: 6768139
    Abstract: A transistor configuration for a bandgap circuit is configured in the form of an npn transistor. An insulated p-type well, which is surrounded by a buried n-type well, is used as a base terminal. The n-type well constitutes the emitter terminal. A negatively doped region, which acts as a collector terminal, is formed in the p-type well. The structure that is used exists in DRAM processes, and it can therefore be used to form an npn transistor as a footprint diode in bandgap circuits.
    Type: Grant
    Filed: August 12, 2002
    Date of Patent: July 27, 2004
    Assignee: Infineon Technologies AG
    Inventors: Helmut Fischer, Jürgen Lindolf
  • Patent number: 6762106
    Abstract: An Si/SiGe layer including an Si buffer layer, an SiGe spacer layer, a graded SiGe layer and an Si cap layer is epitaxially grown in a region corresponding to a collector opening while a polycrystalline layer is deposited on the upper surface of a nitride film, and side surfaces of an oxide film and the nitride film. In this case, the Si buffer layer is formed first and then other layers such as the SiGe spacer layer are formed, thereby ensuring non-selective epitaxial growth. Then, a polycrystalline layer is deposited over the nitride film.
    Type: Grant
    Filed: December 23, 2002
    Date of Patent: July 13, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shigetaka Aoki, Tohru Saitoh, Katsuya Nozawa
  • Patent number: 6727146
    Abstract: This semiconductor device manufacturing method comprises the steps of: forming a thick gate oxide film (thick oxide film) in a first region of a substrate, forming a thin gate oxide film (thin oxide layer) in a second region, and then, applying oxynitridation to these gate oxide films; forming gate electrodes to 1d on these gate oxide films; and implanting an ion that contains nitrogen or nitrogen atoms into at least one part of an interface between the hick gate oxide film (thick oxide film) and the substrate before or after the step of forming the gate electrodes, thereby forming a highly oxy-nitrided region. In this manner, in a semiconductor device in which there coexist a MISFET having a thin gate insulation film and a MISFET having a thick gate insulation film, hot carrier reliability of the MISFET having the thick gate insulation film is improved.
    Type: Grant
    Filed: November 6, 2002
    Date of Patent: April 27, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Eiichi Murakami, Akio Nishida, Kazunori Umeda, Kousuke Okuyama, Toshiaki Yamanaka, Jiro Yugami, Shinichiro Kimura