With Base Region Having Specified Doping Concentration Profile Or Specified Configuration (e.g., Inactive Base More Heavily Doped Than Active Base Or Base Region Has Constant Doping Concentration Portion (e.g., Epitaxial Base)) Patents (Class 257/592)
  • Patent number: 7705427
    Abstract: An integrated circuit includes a bipolar transistor comprising a substrate and a collector formed in the substrate. The collector includes a highly doped lateral zone, a very lightly doped central zone and a lightly doped intermediate zone located between the central zone and the lateral zone 4a of the collector. The substrate includes a lightly doped lateral zone and a highly doped central zone. The dopant species in the zone of the substrate are electrically inactive.
    Type: Grant
    Filed: November 15, 2006
    Date of Patent: April 27, 2010
    Assignee: STMicroelectronics SA
    Inventors: Damien Lenoble, Thierry Schwartzmann, Laurence Boissonnet
  • Patent number: 7705426
    Abstract: The present invention provides an integrated semiconductor device that includes a semiconductor substrate, a first device containing a heterojunction bipolar transistor (HBT) located in a first region of the semiconductor substrate, wherein the HBT includes a base region containing a first portion of a SiGe or SiGeC layer, and a second device located in a second region of the semiconductor substrate, wherein the second device includes an interconnect containing a second portion of the SiGe or SiGeC layer. In a specific embodiment of the present invention, the second device is a memory device including a trench capacitor and a field effect transistor (FET) that are electrically connected together by the second portion of the SiGe or SiGeC layer. Alternatively, the second device is a trench-biased PNPN silicon controlled rectifier (SCR). The present invention also provides a novel reversibly programmable device or a novel memory device formed by a novel trench-biased SCR device.
    Type: Grant
    Filed: November 10, 2006
    Date of Patent: April 27, 2010
    Assignee: International Business Machines Corporation
    Inventor: Steven Voldman
  • Patent number: 7692269
    Abstract: A vertical organic transistor and a method for fabricating the same are provided, wherein an emitter, a grid with openings and a collector are sequentially arranged above a substrate. Two organic semiconductor layers are interposed respectively between the emitter and the grid with openings and between the grid with openings and the collector. The channel length is simply decided by the thickness of the organic semiconductor layers. The collector current depends on the space-charge-limited current contributed by the potential difference between the emitter and the openings of the grid. And the grid voltage can thus effectively control the collector current. Further, the fabrication process of the vertical organic transistor of the present invention is simple and exempt from using the photolithographic process.
    Type: Grant
    Filed: February 15, 2007
    Date of Patent: April 6, 2010
    Assignee: National Chiao Tung University
    Inventors: Hsin-Fei Meng, Sheng-Fu Horng, Yu-Chiang Chao
  • Patent number: 7687887
    Abstract: A method for forming a self-aligned bipolar transistor structure uses the selective growth of a doped silicon emitter in a sloped oxide emitter window to form the self-aligned structure. In an alternate process flow, the top emitter layer is SiGe with a high Ge content that is etched off selectively after deposition of the extrinsic base layer. In another alternate flow, a nitride plug formed on top of the emitter blocks the extrinsic base implant from the emitter region.
    Type: Grant
    Filed: December 1, 2006
    Date of Patent: March 30, 2010
    Assignee: National Semiconductor Corporation
    Inventors: Monir El-Diwany, Alexei Sadovnikov, Jamal Ramdani
  • Patent number: 7671447
    Abstract: The invention relates to a semiconductor device (10) with a semiconductor body (12) comprising a bipolar transistor with an emitter region (1), a base region (2) and a collector region (3) of, respectively, a first conductivity type, a second conductivity type, opposite to the first conductivity type, and the first conductivity type, wherein, viewed in projection, the emitter region (1) is positioned above or below the base region (2), and the collector region (3) laterally borders the base region (2). According to the invention, the base region (2) comprises a highly doped subregion (2A) the doping concentration of which has a delta-shaped profile in the thickness direction, and said highly doped sub-region (2A) extends laterally as far as the collector region (3). Such a lateral bipolar transistor has excellent high-frequency properties and a relatively high breakdown voltage between the base and collector regions (2, 3), implying that the device is suitable for high power applications.
    Type: Grant
    Filed: July 7, 2005
    Date of Patent: March 2, 2010
    Assignee: NXP B.V.
    Inventors: Andreas Hubertus Montree, Jan Willem Slotboom, Prabhat Agarwal, Philippe Meunier-Beillard
  • Patent number: 7667295
    Abstract: In a semiconductor device including a bipolar transistor, a base region has a two layer structure including a first base region, and a second base region which is provided around the first base region and has a lower impurity density than that of the first base region and has a shallower depth than that of the first base region.
    Type: Grant
    Filed: May 16, 2008
    Date of Patent: February 23, 2010
    Assignee: NEC Electronics Corporation
    Inventor: Hiroki Fujii
  • Patent number: 7652288
    Abstract: A method and apparatus for depositing single crystal, epitaxial films of silicon carbon and silicon germanium carbon on a plurality of substrates in a hot wall, isothermal UHV-CVD system is described. In particular, a multiple wafer low temperature growth technique in the range from 350° C. to 750° C. is described for incorporating carbon epitaxially in Si and SiGe films with very abrupt and well defined junctions, but without any associated oxygen background contamination. Preferably, these epitaxial SiC and SiGeC films are in-situ doped p- or n-type and with the presence of low concentration of carbon <1020 cm?3, the as-grown p- or n-type dopant profile can withstand furnace anneals to temperatures of 850° C. and rapid thermal anneal temperatures to 1000° C.
    Type: Grant
    Filed: June 27, 2008
    Date of Patent: January 26, 2010
    Assignee: International Business Machines Corporation
    Inventors: Jack O. Chu, Basanth Jaqannathan, Alfred Grill, Bernard S. Meyerson, John A. Ott
  • Patent number: 7629628
    Abstract: A transistor includes an emitter, a collector, and a base layer having a base contact. The base layer includes an intrinsic region between the emitter and the collector, an extrinsic region between the intrinsic region and the base contact, and a first doping layer that is doped with a trivalent substance, that extends into the extrinsic region, and that is counter-doped with a pentavalent substance in a region adjacent to the emitter.
    Type: Grant
    Filed: December 20, 2002
    Date of Patent: December 8, 2009
    Assignee: Austriamicrosystems AG
    Inventors: Jochen Kraft, Bernhard Loeffler, Georg Roehrer
  • Patent number: 7622790
    Abstract: A transistor assembly having a transistor includes a plurality of transistor regions, each of which has a vertical transistor structure having a collector semiconductor region, a base semiconductor region and an emitter semiconductor region, emitter contacting regions arranged above the transistor regions and base contacting regions connected to the base semiconductor regions via a polycrystalline semiconductor layer, wherein the polycrystalline semiconductor layer is structured such that the base contacting regions of transistor regions which are not part of the transistor are electrically isolated from base contacting regions of transistor regions which are part of the transistor.
    Type: Grant
    Filed: May 11, 2005
    Date of Patent: November 24, 2009
    Assignee: Infineon Technologies AG
    Inventor: Jakob Huber
  • Patent number: 7615455
    Abstract: A bipolar transistor having a base region resting by its lower surface on a collector region and surrounded with a first insulating layer, a base contact conductive region in contact with an external upper peripheral region of the base region, a second insulating region in contact with an intermediary upper peripheral region of the base region, an emitter region in contact with the central portion of the base region. The level of the central portion is higher than the level of the intermediary portion.
    Type: Grant
    Filed: September 19, 2006
    Date of Patent: November 10, 2009
    Assignee: STMicroelectronics S.A.
    Inventors: Pascal Chevalier, Alain Chantre
  • Patent number: 7612430
    Abstract: The silicon bipolar transistor (100) comprises a base, with a first highly-doped base layer (105) and a second poorly-doped base layer (106) which together form the base. The emitter is completely highly-doped and mounted directly on the second base layer (106).
    Type: Grant
    Filed: June 15, 2001
    Date of Patent: November 3, 2009
    Assignee: Infineon Technologies AG
    Inventors: Martin Franosch, Thomas Meister, Herbert Schäfer, Reinhard Stengl, Konrad Wolf
  • Publication number: 20090261385
    Abstract: A bipolar transistor includes a base layer design and a method for fabricating such a bipolar transistor that employ a built-in accelerating field focused on a base region adjacent to a collector, where minority carrier transport is otherwise retarded. The accelerating field of the base layer includes on average, a relatively low p-doping level in a first region proximate to the collector and a relatively high p-doping level in a second region proximate to an emitter. Alternatively, the accelerating field can be derived from band gap grading, wherein the grade of band gap in the first region is greater than the grade of band gap in the second region, and the average band gap of the first region is lower than that of the second region.
    Type: Application
    Filed: June 24, 2009
    Publication date: October 22, 2009
    Applicant: Kopin Corporation
    Inventors: Eric M. Rehder, Roger E. Welser, Charles R. Lutz
  • Patent number: 7582536
    Abstract: An electronic device contains a substrate, a sub-collector supported by the substrate, an un-doped layer having a selectively implanted buried sub-collector and supported by the sub-collector, an As-based nucleation layer partially supported by the un-doped layer, a collector layer supported by the As-based nucleation layer, a base layer supported by the collector layer, an emitter layer and a base contact supported by the base layer, an emitter cap layer supported by the emitter layer, an emitter contact supported by the emitter cap layer, and a collector contact supported by the sub-collector. A method provides for selecting a first InP layer, forming an As-based nucleation layer on the first InP layer, and epitaxially growing a second InP layer on the As-based nucleation layer.
    Type: Grant
    Filed: August 14, 2008
    Date of Patent: September 1, 2009
    Assignee: HRL Laboratories, LLC
    Inventors: Rajesh D. Rajavel, Mary Y. Chen, Steven S. Bui, David H. Chow, James Chingwei Li, Mehran Mokhtari, Marko Sokolich
  • Patent number: 7579635
    Abstract: A base layer made of SiGe mixed crystal includes a spacer layer formed in contact with a collector layer with no base impurities diffused therein and an intrinsic base layer formed in contact with an emitter layer with base impurities diffused therein. The spacer layer contains C at a low concentration. The intrinsic base layer has a first region containing C at a low concentration on the collector side and a second region containing C at a high concentration on the emitter side.
    Type: Grant
    Filed: January 7, 2008
    Date of Patent: August 25, 2009
    Assignee: Panasonic Corporation
    Inventor: Shigetaka Aoki
  • Patent number: 7575942
    Abstract: An epitaxial substrate used to generate a group III nitride crystal having excellent crystal quality. An upper layer of a group III nitride is formed on a sapphire base with an off angle, and after that a heating process is performed at a temperature not lower than 1500° C., and thereby, the crystal quality of the upper layer is improved and repeating steps of which the size is greater than the height of several atomic layers are provided on the surface of the upper layer. The obtained epitaxial substrate is used as a base substrate for growing a group III nitride crystal layer. The group III nitride crystal grows in a manner of step flow, and therefore, threading dislocations from the upper layer are bent according to this growth, and are unevenly distributed as the crystal grows afterwards.
    Type: Grant
    Filed: May 4, 2006
    Date of Patent: August 18, 2009
    Assignee: NGK Insulators, Ltd.
    Inventor: Tomohiko Shibata
  • Patent number: 7566948
    Abstract: A bipolar transistor includes a base layer design and a method for fabricating such a bipolar transistor that employ a built-in accelerating field focused on a base region adjacent to a collector, where minority carrier transport is otherwise retarded. The accelerating field of the base layer includes on average, a relatively low p-doping level in a first region proximate to the collector and a relatively high p-doping level in a second region proximate to an emitter. Alternatively, the accelerating field can be derived from band gap grading, wherein the grade of band gap in the first region is greater than the grade of band gap in the second region, and the average band gap of the first region is lower than that of the second region.
    Type: Grant
    Filed: October 20, 2004
    Date of Patent: July 28, 2009
    Assignee: Kopin Corporation
    Inventors: Eric M. Rehder, Roger E. Welser, Charles R. Lutz
  • Patent number: 7547959
    Abstract: An improved bipolar junction transistor and a method for manufacturing the same are provided. The bipolar junction transistor includes: a buried layer and a high concentration N-type collector region in a P-type semiconductor substrate; a low concentration P-type base region in the semiconductor substrate above the buried layer; a first high concentration P-type base region along an edge of the low concentration P-type base region; a second high concentration P-type base region at a center of the low concentration P-type base region; a high concentration N-type emitter region between the first and second high concentration base regions; and insulating layer spacers between the high concentration base regions and the high concentration emitter regions. In the bipolar junction transistor, the emitter-base distance can be reduced using a trench and an insulating layer spacer. This may improve base voltage and high-speed response characteristics.
    Type: Grant
    Filed: December 27, 2006
    Date of Patent: June 16, 2009
    Assignee: Dongbu Electronics Co., Ltd.
    Inventor: Nam Joo Kim
  • Publication number: 20090146258
    Abstract: A structure and a process for a self-aligned vertical PNP transistor for high performance SiGe CBiCMOS process. Embodiments include SiGe CBiCMOS with high-performance SiGe NPN transistors and PNP transistors. As the PNP transistors and NPN transistors contained different types of impurity profile, they need separate lithography and doping step for each transistor. The process is easy to integrate with existing CMOS process to save manufacturing time and cost. As plug-in module, fully integration with SiGe BiCMOS processes. High doping Polysilicon Emitter can increase hole injection efficiency from emitter to base, reduce emitter resistor, and form very shallow EB junction. Self-aligned N+ base implant can reduce base resistor and parasitical EB capacitor. Very low collector resistor benefits from BP layer. PNP transistor can be Isolated from other CMOS and NPN devices by BNwell, Nwell and BN+ junction.
    Type: Application
    Filed: February 9, 2009
    Publication date: June 11, 2009
    Applicant: CHARTERED SEMICONDUCTOR MANUFACTURING, LTD.
    Inventors: Shaoqiang ZHANG, Purakh Raj VERMA, Sanford CHU
  • Patent number: 7541624
    Abstract: A method for fabricating a bipolar transistor includes forming collector, base, and emitter semiconductor layers on a substrate such that the layers form a vertical sequence with respect to an adjacent surface of the substrate. The method includes etching away a portion of a top one of the semiconductor layers to expose a portion of the base semiconductor layer and then, growing semiconductor on the exposed portion of the base layer. The top one of the semiconductor layers is the layer of the sequence that is located farthest from the substrate. The growing causes grown semiconductor to laterally surround a vertical portion of the top one of the semiconductor layers.
    Type: Grant
    Filed: July 21, 2003
    Date of Patent: June 2, 2009
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Young-Kai Chen, Rose Fasano Kopf, Wei-Jer Sung, Nils Guenter Weimann
  • Patent number: 7538412
    Abstract: A semiconductor device includes a semiconductor material, the semiconductor material including a base region and a field stop zone including a first side adjacent the base region and a second side opposite the first side. The field stop zone includes a first dopant implant and a second dopant implant. The first dopant implant has a first dopant concentration maximum and the second dopant implant has a second dopant concentration maximum with the first dopant concentration maximum being less than the second dopant concentration maximum, and being located closer to the second side than the second dopant concentration maximum.
    Type: Grant
    Filed: June 30, 2006
    Date of Patent: May 26, 2009
    Assignee: Infineon Technologies Austria AG
    Inventors: Hans-Joachim Schulze, Franz-Josef Niedernostheide, Helmut Strack, Carsten Schaeffer, Frank Pfirsch
  • Patent number: 7531851
    Abstract: An electronic device contains a substrate, a sub-collector supported by the substrate, an un-doped layer having a selectively implanted buried sub-collector and supported by the sub-collector, an As-based nucleation layer partially supported by the un-doped layer, a collector layer supported by the As-based nucleation layer, a base layer supported by the collector layer, an emitter layer and a base contact supported by the base layer, an emitter cap layer supported by the emitter layer, an emitter contact supported by the emitter cap layer, and a collector contact supported by the sub-collector. A method provides for selecting a first InP layer, forming an As-based nucleation layer on the first InP layer, and epitaxially growing a second InP layer on the As-based nucleation layer.
    Type: Grant
    Filed: February 28, 2007
    Date of Patent: May 12, 2009
    Assignee: HRL Laboratories, LLC
    Inventors: Rajesh D. Rajavel, Mary Y. Chen, Steven S. Bui, David H. Chow, James Chingwei Li, Mehran Mokhtari, Marko Sokolich
  • Patent number: 7521327
    Abstract: A high fT and fmax bipolar transistor includes an emitter, a base, and a collector. The emitter has a lower portion and an upper portion that extends beyond the lower portion. The base includes an intrinsic base and an extrinsic base. The intrinsic base is located between the lower portion of the emitter and the collector. The extrinsic base extends from the lower portion of the emitter beyond the upper portion of the emitter and includes a continuous conductor that extends from underneath the upper portion of the emitter and out from underneath the upper portion of the emitter. The continuous conductor provides a low electrical resistance path from a base contact (not shown) to the intrinsic base. The transistor may include a second conductor that does not extend underneath the upper portion of the emitter, but which further reduces the electrical resistance through the extrinsic base.
    Type: Grant
    Filed: March 17, 2006
    Date of Patent: April 21, 2009
    Assignee: International Business Machines Corporation
    Inventors: Alvin Jose Joseph, Qizhi Liu
  • Patent number: 7495264
    Abstract: A semiconductor device has a substrate and a dielectric film formed directly or indirectly on the substrate. The dielectric film contains a metal silicate film, and a silicon concentration in the metal silicate film is lower in a center portion in the film thickness direction than in an upper portion and in a lower portion.
    Type: Grant
    Filed: December 7, 2006
    Date of Patent: February 24, 2009
    Assignee: NEC Corporation
    Inventors: Heiji Watanabe, Haruhiko Ono, Nobuyuki Ikarashi
  • Publication number: 20090026578
    Abstract: A vertical NPN bipolar transistor includes a P-type semiconductor structure, an N-well as the collector, a P-Base region in the N-well and an N-type region as the emitter. The transistor further includes P-type region formed in the P-Base region and underneath the field oxide layer where the P-type region has a doping concentration higher than the P-base region. The P-type region functions to inhibit the lateral parasitic bipolar action so that the transistor action is confined to the intrinsic base region vertically underneath the emitter. In one embodiment, the P-type region is a boron field doping region. The boron field doping region can be the same field doping region used to form channel stops for NMOS transistors in a CMOS fabrication process.
    Type: Application
    Filed: July 27, 2007
    Publication date: January 29, 2009
    Applicant: MICREL, INC.
    Inventors: Schyi-yi Wu, Martin Alter
  • Patent number: 7479438
    Abstract: The invention, in one aspect, provides a semiconductor device that comprises a bipolar transistor located over and within a semiconductor substrate, a collector located within a tub of the bipolar transistor and having an amorphous region formed at least partially therein, a base located over the collector, and an emitter located over the base. There is also provided a method of fabricating the semiconductor device.
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: January 20, 2009
    Assignee: Agere Systems Inc.
    Inventors: Alan S. Chen, Mark Dyson, Daniel C. Kerr, Nace M. Rossi
  • Patent number: 7466010
    Abstract: The present invention provides a bipolar transistor having a raised extrinsic base silicide and an emitter contact border that are self-aligned. The bipolar transistor of the present invention exhibit reduced parasitics as compared with bipolar transistors that do not include a self-aligned silicide and a self-aligned emitter contact border. The present invention also is related to methods of fabricating the inventive bipolar transistor structure. In the methods of the present invention, a block emitter polysilicon region replaces a conventional T-shaped emitter polysilicon.
    Type: Grant
    Filed: July 5, 2005
    Date of Patent: December 16, 2008
    Assignee: International Business Machines Corporation
    Inventors: David C. Ahlgren, Gregory G. Freeman, Marwan H. Khater, Richard P. Volant
  • Publication number: 20080283967
    Abstract: In a semiconductor device including a bipolar transistor, a base region has a two layer structure including a first base region, and a second base region which is provided around the first base region and has a lower impurity density than that of the first base region and has a shallower depth than that of the first base region.
    Type: Application
    Filed: May 16, 2008
    Publication date: November 20, 2008
    Applicant: NEC ELECTRONICS CORPORATION
    Inventor: Hiroki Fujii
  • Patent number: 7446012
    Abstract: The present invention relates to a lateral PNP transistor and the method of manufacturing the same. The medium doping N-type base area and the light doping P? collector area were first introduced in the structure before the formation of P+ doping emitter area and the collector area. The emitter-base-collector doping profile in the lateral and the base width of LPNP were similar to NPN. The designer can optimize the doping profile and area size of each area according to the request of the current gain (Hfe), collector-base breakdown voltage (BVceo), and early voltage (VA) of LPNP transistor. These advantages may cause to reduce the area and enhance performance of the LPNP transistor.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: November 4, 2008
    Assignee: BCD Semiconductor Manufacturing Limited
    Inventors: Chong Ren, Xian-Feng Liu, Bin Qiu
  • Patent number: 7446376
    Abstract: In an insulated gate bipolar transistor, an improved safe operating area capability is achieved according to the invention by a two-fold base region comprising a first base region (81), which is disposed in the channel region (7) so that it encompasses the one or more source regions (6), but does not adjoin the second main surface underneath the gate oxide layer (41), and a second base region (82) is disposed in the semiconductor substrate (2) underneath the base contact area (821) so that it partially overlaps with the channel region (7) and with the first base region (81).
    Type: Grant
    Filed: November 16, 2004
    Date of Patent: November 4, 2008
    Assignee: ABB Technology AG
    Inventors: Munaf Rahimo, Stefan Linder
  • Publication number: 20080265282
    Abstract: Disclosed is an improved semiconductor structure (e.g., a silicon germanium (SiGe) hetero-junction bipolar transistor) having a narrow essentially interstitial-free SIC pedestal with minimal overlap of the extrinsic base. Also, disclosed is a method of forming the transistor which uses laser annealing, as opposed to rapid thermal annealing, of the SIC pedestal to produce both a narrow SIC pedestal and an essentially interstitial-free collector. Thus, the resulting SiGe HBT transistor can be produced with narrower base and collector space-charge regions than can be achieved with conventional technology.
    Type: Application
    Filed: April 30, 2007
    Publication date: October 30, 2008
    Inventors: Oleg Gluschenkov, Rajendran Krishnasamy, Kathryn T. Schonenberg
  • Patent number: 7439608
    Abstract: Described herein are embodiments of a bipolar junction transistor including a plurality of base terminal rings having an emitter terminal ring between any two base terminal rings of the plurality of base terminal rings, and a collector terminal ring surrounding the plurality of base terminal rings and the emitter terminal ring and methods of manufacturing the same.
    Type: Grant
    Filed: September 22, 2006
    Date of Patent: October 21, 2008
    Assignee: Intel Corporation
    Inventor: Kevin E. Arendt
  • Publication number: 20080217742
    Abstract: Bipolar transistor device structures that improve bipolar device reliability with little or no negative impact on device performance. In one embodiment, the bipolar device has a collector of first conductivity type material formed in a substrate, a base of a second conductivity type material including an extrinsic base layer and an intrinsic base layer, a raised emitter of a first conductivity type semiconductor material formed on the intrinsic base layer, and, a dielectric material layer separating the intrinsic base region and the raised emitter region, and, a thin “shunt” layer of dopant of second conductivity type material added to the region below the emitter dielectric layer. In a second embodiment, a selectively implanted collector (pedestal implant) is added to the vertical bipolar transistor device to enable a reduction in overall subcollector doping level to improve reliability without sacrificing device performance.
    Type: Application
    Filed: March 9, 2007
    Publication date: September 11, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Jeffrey B. Johnson, Edward J. Nowak, Andreas D. Stricker, Benjamin T. Voegeli
  • Publication number: 20080191316
    Abstract: A semiconductor transistor device includes a drift region, an insulating structure, a gate insulator, a gate electrode, a source, and a drain. The drift region includes a first lateral portion having a first dopant concentration and a second lateral portion having a second dopant concentration that is higher than the first lateral portion. The insulating structure is formed on the drift region and is disposed over a border between the first and second lateral portions such that hole generation is minimized in the drift region during operation.
    Type: Application
    Filed: February 14, 2008
    Publication date: August 14, 2008
    Inventor: Mueng-Ryul Lee
  • Patent number: 7378325
    Abstract: A high voltage semiconductor device having a high current gain hFE is formed with a collector region (20) of a first conduction type, an emitter region (40) of the first conduction type, and a base region (30) of a second conduction type opposite to the first conduction type located between the collector region and the emitter region. The free carrier density of the base region (30) where no depletion layer is formed is smaller than the space charge density of a depletion layer formed in the base region (30).
    Type: Grant
    Filed: May 23, 2006
    Date of Patent: May 27, 2008
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Saichirou Kaneko, Masakatsu Hoshi, Yoshinori Murakami, Tetsuya Hayashi, Hideaki Tanaka
  • Patent number: 7375410
    Abstract: The present invention provides a “collector-less” silicon-on-insulator (SOI) bipolar junction transistor (BJT) that has no impurity-doped collector. Instead, the inventive vertical SOI BJT uses a back gate-induced, minority carrier inversion layer as the intrinsic collector when it operates. In accordance with the present invention, the SOI substrate is biased such that an inversion layer is formed at the bottom of the base region serving as the collector. The advantage of such a device is its CMOS-like process. Therefore, the integration scheme can be simplified and the manufacturing cost can be significantly reduced. The present invention also provides a method of fabricating BJTs on selected areas of a very thin BOX using a conventional SOI starting wafer with a thick BOX. The reduced BOX thickness underneath the bipolar devices allows for a significantly reduced substrate bias compatible with the CMOS to be applied while maintaining the advantages of a thick BOX underneath the CMOS.
    Type: Grant
    Filed: February 25, 2004
    Date of Patent: May 20, 2008
    Assignee: International Business Machines Corporation
    Inventors: Herbert L. Ho, Mahender Kumar, Qiqing Ouyang, Paul A. Papworth, Christopher D. Sheraw, Michael D. Steigerwalt
  • Patent number: 7342293
    Abstract: The present invention relates to bipolar junction transistors (BJTS). The collector region of each BJT is located in a semiconductor substrate surface and adjacent to a first shallow trench isolation (STI) region. A second STI region is provided, which extends between the first STI region and the collection region and undercuts a portion of the active base region with an undercut angle of not more than about 90°. For example, the second STI region may a substantially triangular cross-section with an undercut angle of less than about 90°, or a substantially rectangular cross-section with an undercut angle of about 90°. Such a second STI region can be fabricated using a porous surface section formed in an upper surface of the collector region.
    Type: Grant
    Filed: December 5, 2005
    Date of Patent: March 11, 2008
    Assignee: International Business Machines Corporation
    Inventors: Thomas A. Wallner, Thomas N. Adam, Stephen W. Bedell, Joel P. De Souza
  • Patent number: 7327012
    Abstract: A method of forming bipolar transistors by using the same mask to form the collector region in a substrate of an opposite conductivity type as to form the base in the collector region. More specifically, impurities of a first conductivity type are introduced into a region of a substrate of a second conductivity type through a first aperture in a first mask to form a collector region. Impurities of the second conductivity type are introduced in the collector through the first aperture in the first mask to form the base region. Impurities of the first conductivity type are then introduced into the base region through a second aperture in a second mask to form the emitter region. The minimum dimension of the first aperture of the first mask is selected for a desired collector to base breakdown voltage. This allows tuning of the breakdown voltage.
    Type: Grant
    Filed: May 17, 2006
    Date of Patent: February 5, 2008
    Inventor: James Douglas Beasom
  • Patent number: 7291898
    Abstract: According to one exemplary embodiment, a bipolar transistor includes an active area situated between first and second isolation regions in a substrate. The bipolar transistor further includes an epitaxial extension layer situated on the active area, where the epitaxial extension layer extends over the first and second isolation regions. The bipolar transistor further includes a base layer situated on the epitaxial extension layer, where the base layer includes an epitaxial base, and where the epitaxial base includes a usable emitter formation area. The active area has a first width and the usable emitter formation area has a second width, where the second width is at least as large as the first width.
    Type: Grant
    Filed: June 6, 2005
    Date of Patent: November 6, 2007
    Assignee: Newport Fab, LLC
    Inventor: Greg D. U'Ren
  • Patent number: 7288829
    Abstract: Disclosed is a method of forming a transistor in an integrated circuit structure that begins by forming a collector in a substrate and an intrinsic base above the collector. Then, the invention patterns an emitter pedestal for the lower portion of the emitter on the substrate above the intrinsic base. Before actually forming the emitter or associates spacer, the invention forms an extrinsic base in regions of the substrate not protected by the emitter pedestal. After this, the invention removes the emitter pedestal and eventually forms the emitter where the emitter pedestal was positioned.
    Type: Grant
    Filed: November 10, 2004
    Date of Patent: October 30, 2007
    Assignee: International Business Machines Corporation
    Inventors: Marwan H Khater, Francois Pagette
  • Patent number: 7285830
    Abstract: An improved lateral bipolar junction transistor and a method of forming such a lateral bipolar transistor without added mask in CMOS flow on a p-substrate are disclosed. The CMOS flow includes patterning and n-well implants; pattern and implant pocket implants for core nMOS and MOS; pattern and implants pocket implants I/O nMOS and pMOS; sidewall deposit and etch and then source/drain pattern and implant for nMOS and pMOS. The bipolar transistor is formed by forming emitter and collector contacts by implants used in source/drain regions; forming an emitter by implants done in core pMOS during core pMOS LDD extender; and forming part of an base by pocket implant steps.
    Type: Grant
    Filed: September 30, 2005
    Date of Patent: October 23, 2007
    Assignee: Texas Instruments Incorporated
    Inventor: Amitava Chatterjee
  • Patent number: 7268412
    Abstract: A bipolar transistor with a substrate having a collector region and a base structure provided thereon. An emitter structure is formed over the base structure and an extrinsic base structure is formed over the base structure and over the collector region beside and spaced from the emitter structure. A dielectric layer is deposited over the substrate and connections are formed to the extrinsic base structure, the emitter structure and the collector region.
    Type: Grant
    Filed: February 12, 2005
    Date of Patent: September 11, 2007
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Purakh Raj Verma, Shao-fu Sanford Chu
  • Patent number: 7262483
    Abstract: By a non-selective epitaxial growth method, an SiGe film is grown on the whole surface of a silicon oxide film so as to cover an inner wall of a base opening. Here, such film forming conditions are selected that, inside the base opening, a bottom portion is formed of single crystal, other portions such as a sidewall portion are formed of polycrystalline, and a film thickness of the sidewall portion is less than or equal to 1.5 times the film thickness of the bottom portion. In this non-selective epitaxial growth, monosilane, hydrogen, diborane, and germane are used as source gases. Then, flow rates of monosilane and hydrogen are set to 20 sccm and 20 slm respectively. Also, a growth temperature is set to 650° C., a flow rate of diborane is set to 75 sccm, and a flow rate of germane is set to 35 sccm.
    Type: Grant
    Filed: April 29, 2005
    Date of Patent: August 28, 2007
    Assignee: Fujitsu Limited
    Inventors: Hidekazu Sato, Toshihiro Wakabayashi
  • Patent number: 7253498
    Abstract: The present invention is generally directed to bipolar transistors with geometry optimized for device performance and various methods of making same. In one illustrative embodiment, the device includes a substrate, an intrinsic base region formed in the substrate, a continuous emitter region formed within the intrinsic base region, the emitter region having a plurality of substantially hexagonal shaped openings defined therein, and a plurality of extrinsic base regions formed in the substrate, wherein each of the extrinsic base regions is positioned within an area defined by one of the plurality of substantially hexagonal shaped openings.
    Type: Grant
    Filed: July 6, 2004
    Date of Patent: August 7, 2007
    Assignee: Legerity Inc.
    Inventor: Ranadeep Dutta
  • Patent number: 7247925
    Abstract: A semiconductor device includes a semiconductor substrate of a first conductive type, a collector layer formed on the semiconductor substrate and made of a first semiconductor being of the first conductive type and having a higher resistance than that of the semiconductor substrate, an intrinsic base region having a junction surface with the collector layer and made of a second semiconductor of a second conductive type, and an emitter region having a junction surface with the intrinsic base region and made of a third semiconductor of the first conductive type. A periphery of the intrinsic base region is surrounded by an insulating region extending from the collector layer to the semiconductor substrate.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: July 24, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yasuyuki Toyoda, Shinichi Sonetaka
  • Patent number: 7247926
    Abstract: A high-frequency switching transistor comprises a collector area, which has a first conductivity type, a first barrier area bordering on the collector area, which has a second conductivity type which differs from the first conductivity type, and a semiconductor area bordering on the first barrier area, which has a dopant concentration which is lower than a dopant concentration of the first barrier area. Further, the high-frequency switching transistor has a second barrier area bordering on the semiconductor area, which has a first conductivity type, as well as a base area bordering on the second barrier area, which has a second conductivity type. Additionally, the high-frequency switching transistor comprises a third barrier area bordering on the semiconductor area, which has the second conductivity type and a higher dopant concentration than the semiconductor area. Further, the high-frequency switching transistor has an emitter area bordering on the third barrier area, which has the first conductivity type.
    Type: Grant
    Filed: December 8, 2004
    Date of Patent: July 24, 2007
    Assignee: Infineon Technologies AG
    Inventor: Reinhard Losehand
  • Patent number: 7235861
    Abstract: A method for fabricating an NPN bipolar transistor comprises forming a base layer on a top surface of a substrate. The NPN bipolar transistor may be an NPN silicon-germanium heterojunction bipolar transistor. The method for fabricating the NPN bipolar transistor may further comprise a cap layer situated over the base layer. According to this embodiment, the method for fabricating the NPN bipolar transistor further comprises fabricating an emitter over the base layer, where the emitter defines an intrinsic and an extrinsic base region of the base layer. The emitter may comprise, for example, polycrystalline silicon. The method for fabricating the NPN bipolar transistor further comprises implanting germanium in the extrinsic base region of the base layer so as to make the extrinsic base region substantially amorphous. The method for fabricating the NPN bipolar transistor further comprises implanting boron in the extrinsic base region of the base layer.
    Type: Grant
    Filed: December 2, 2004
    Date of Patent: June 26, 2007
    Assignee: Newport Fab, LLC
    Inventors: David Howard, Marco Racanelli, Greg D. U'Ren
  • Patent number: 7183627
    Abstract: In one embodiment a precursor gas for growing a polycrystalline silicon-germanium region and a single crystal silicon-germanium region is supplied. The precursor gas can be, for example, GeH4. The polycrystalline silicon-germanium region can be, for example, a base contact in a heterojunction bipolar transistor while the single crystal silicon-germanium region can be, for example, a base in the heterojunction bipolar transistor. The polycrystalline silicon-germanium region can be grown in a mass controlled mode at a certain temperature and a certain pressure of the precursor gas while the single crystal silicon-germanium region can be grown, concurrently, in a kinetically controlled mode at the same temperature and the same pressure of the precursor gas. The disclosed embodiments result in controlling the growth of the polycrystalline silicon-germanium independent of the growth of the single crystal silicon-germanium.
    Type: Grant
    Filed: January 22, 2002
    Date of Patent: February 27, 2007
    Assignee: Newport Fab, LLC
    Inventor: Gregory D. U'ren
  • Patent number: 7180159
    Abstract: A bipolar transistor in a monocrystalline semiconductor substrate (101), which has a first conductivity type and includes a surface layer (102) of the opposite conductivity type. The transistor comprises an emitter contact (110) on the surface layer; a base contact (130 and 131) extending through a substantial portion (141) of the surface layer, spaced apart (140a) from the emitter; an insulator region (150/151) buried under the base contact; a collector contact (120); and a first polycrystalline semiconductor region (152/153) selectively located under the insulator region, and a second polycrystalline semiconductor region (154) selectively located under the collector contact. These polycrystalline regions exhibit heavy dopant concentrations of the first conductivity type; consequently, they lower the collector resistance.
    Type: Grant
    Filed: July 13, 2004
    Date of Patent: February 20, 2007
    Assignee: Texas Instruments Incorporated
    Inventor: Gregory E. Howard
  • Patent number: 7173316
    Abstract: An N type semiconductor layer is epitaxially grown on a P type semiconductor substrate of which one end is grounded, and an element isolation layer made of a P type diffusion layer is formed by means of diffusion around the N type semiconductor layer in order to electrically isolate the N type semiconductor layer. The metal layer which is located above the N type semiconductor layer and which forms a wire or a bonding pad is isolated from the N type semiconductor layer in which a diffusion layer or the like has been formed by an insulating film. An N type buried diffusion layer having an impurity concentration higher than that of the N type semiconductor layer is provided between the P type semiconductor substrate and the N type semiconductor layer. In addition, a P type semiconductor layer is formed by means of diffusion between the insulating film and the N type semiconductor layer plus the element isolation layer.
    Type: Grant
    Filed: December 6, 2004
    Date of Patent: February 6, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Yuichi Tateyama
  • Patent number: 7173274
    Abstract: A SiGe bipolar transistor containing substantially no dislocation defects present between the emitter and collector region and a method of forming the same are provided. The SiGe bipolar transistor includes a collector region of a first conductivity type; a SiGe base region formed on a portion of said collector region; and an emitter region of said first conductivity type formed over a portion of said base region, wherein said collector region and said base region include carbon continuously therein. The SiGe base region is further doped with boron.
    Type: Grant
    Filed: September 29, 2004
    Date of Patent: February 6, 2007
    Assignee: International Business Machines Corporation
    Inventors: Jack Oon Chu, Douglas Duane Coolbaugh, James Stuart Dunn, David R. Greenberg, David L. Harame, Basanth Jagannathan, Robb Allen Johnson, Louis D. Lanzerotti, Kathryn Turner Schonenberg, Ryan Wayne Wuthrich