With Bipolar Transistor Structure Patents (Class 257/552)
  • Publication number: 20030034545
    Abstract: High quality epitaxial layers of monocrystalline materials can be grown overlying monocrystalline substrates such as large silicon wafers by forming a compliant substrate for growing the monocrystalline layers. An accommodating buffer layer comprises a layer of monocrystalline oxide spaced apart from a silicon wafer by an amorphous interface layer of silicon oxide. The amorphous interface layer dissipates strain and permits the growth of a high quality monocrystalline oxide accommodating buffer layer. The accommodating buffer layer is lattice matched to both the underlying silicon wafer and the overlying monocrystalline material layer. Any lattice mismatch between the accommodating buffer layer and the underlying silicon substrate is taken care of by the amorphous interface layer. In addition, formation of a compliant substrate may include utilizing surfactant enhanced epitaxy, epitaxial growth of single crystal silicon onto single crystal oxide, and epitaxial growth of Zintl phase materials.
    Type: Application
    Filed: August 16, 2001
    Publication date: February 20, 2003
    Applicant: MOTOROLA, INC.
    Inventors: Timothy J. Johnson, Peter J. Wilson
  • Patent number: 6509625
    Abstract: A guard ring structure formed around the periphery of a bipolar semiconductor device. A guard region (11) is formed in a substrate (1) of the device so as to extend adjacent a peripheral portion of the device. An insulating layer (3) is formed on the substrate between the peripheral portion of the device and the guard region (11). A polysilicon layer (13) is formed on the insulating layer (3) and covered with a layer of densified dielectic (14). Electrical interconnections are provided between the polysilicon layer (13) and the guard region (11) at spaced apart portions of the device where the guard structure does not need to be protected by the densified dielectric.
    Type: Grant
    Filed: May 9, 2001
    Date of Patent: January 21, 2003
    Assignee: Zetex PLC
    Inventor: David Neil Casey
  • Publication number: 20030001234
    Abstract: A semiconductor device in which a vertical pnp-bipolar transistor is formed in a prescribed element region on a semiconductor substrate includes: a buried n+-layer of a high concentration formed in the prescribed element region; and a p-type collector layer formed on the buried n+-layer. By introducing impurities that has a larger diffusion coefficient than the buried n+-layer, the collector layer can be formed on the buried n+-layer formed in common with other element regions, without any special masking.
    Type: Application
    Filed: January 2, 2002
    Publication date: January 2, 2003
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Hidenori Fujii
  • Publication number: 20020168809
    Abstract: A semiconductor device having at least one layer of a group III-V semiconductor material epitaxially deposited on a group III-V nucleation layer adjacent to a germanium substrate. By introducing electrical contacts on one or more layers of the semiconductor device, various optoelectronic and microelectronic circuits may be formed on the semiconductor device having similar quality to conventional group III-V substrates at a substantial cost savings. Alternatively, an active germanium device layer having electrical contacts may be introduced to a portion of the germanium substrate to form an optoelectronic integrated circuit or a dual optoelectronic and microelectronic device on a germanium substrate depending on whether the electrical contacts are coupled with electrical contacts on the germanium substrate and epitaxial layers, thereby increase the functionality of the semiconductor devices.
    Type: Application
    Filed: May 8, 2001
    Publication date: November 14, 2002
    Inventors: Karim S. Boutros, Nasser H. Karam, Dimitri Krut, Moran Haddad
  • Publication number: 20020158308
    Abstract: A semiconductor component and a method for fabricating it includes a substrate and an epitaxial layer situated thereon and integrating at least a first and a second bipolar component in the layer. The first and second bipolar components have a buried layer and different collector widths. The buried layer of the second component has a larger layer thickness than that of the first component; exactly one epitaxial layer is provided. The different collector widths produced as a result thereof are influenced by the outdiffusion of the dopant of the buried layers by other substances.
    Type: Application
    Filed: May 13, 2002
    Publication date: October 31, 2002
    Inventors: Jakob Huber, Wolfgang Klein
  • Publication number: 20020153575
    Abstract: A semiconductor device may include an element isolation region 14, an npn-type bipolar transistor 200, and a p-type field effect transistor 100, which are formed on a SOI substrate. The bi-polar transistor 200 and the field effect transistor 100 are formed in the same element forming region 16. An n-type body region 52a is electrically connected to an n-type collector region 230. A p-type source region 210 is electrically connected to the n-type collector region 230. A p-type drain region 130 is electrically connected to a p-type base region 220.
    Type: Application
    Filed: January 18, 2002
    Publication date: October 24, 2002
    Inventor: Akihiko Ebina
  • Patent number: 6384433
    Abstract: A voltage variable resistor formed on heterojunction bipolar transistor epitaxial material includes a current channel made on emitter material. Emitter mesas separated by a recess provide the contacts for the voltage variable resistor. Each mesa is topped with emitter metal forming the resistor contacts. The emitter mesas are layered on top of the current channel that is layered atop of a base layer. The voltage variable resistor's control contact is provided by a base contact located on the base layer and separated from the current channel.
    Type: Grant
    Filed: March 23, 2000
    Date of Patent: May 7, 2002
    Assignee: RF Micro Devices, Inc.
    Inventors: Curtis A. Barratt, Arthur E. Geissberger, Larry W. Kapitan, Michael T. Fresina, Ramond Jeffrey Vass
  • Patent number: 6376883
    Abstract: The present invention relates to a method of manufacturing a capacitor in a BICMOS integrated circuit manufacturing technology, including the steps of depositing, on a thick oxide region, a polysilicon layer corresponding to a MOS transistor gate electrode; successively depositing a base polysilicon layer and a silicon oxide layer; forming an opening in these last two layers; performing a thermal anneal in an oxidizing atmosphere; depositing a silicon nitride layer and a spacer polysilicon layer; depositing an emitter polysilicon layer; and making a contact with the base polysilicon layer and a contact with the emitter polysilicon layer.
    Type: Grant
    Filed: November 28, 2000
    Date of Patent: April 23, 2002
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventor: Yvon Gris
  • Patent number: 6255713
    Abstract: A current source formed in a p-type substrate is disclose. First, a deep n-well is formed within the p-type substrate and a buried n+ layer is formed within the deep n-well. Next, a p-well is formed within the deep n-well and atop the buried n+ layer. The p-well and deep n-well are then surrounded by an isolation structure that extends from the surface of the substrate to below the level of the p-well. A n+ reference structure is formed within the p-well and a gate is formed above the p-well, the gate separated from the substrate by a thin oxide layer, the gate extending over at least a portion of the n+ reference structure. Finally, a n+ output structure is formed within the p-well. An input reference current is provided to the n+ reference structure and an output current is provided by the n+ output structure.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: July 3, 2001
    Assignee: Taiwan Semiconductor Manufacturing Corporation
    Inventor: Min-hwa Chi
  • Patent number: 6252269
    Abstract: According to a semiconductor memory for one aspect of the present invention, a memory cell transistor is formed in a P-type first well region which is formed at the surface of a P-type semiconductor substrate, and a back bias voltage is applied to the P-type first well region and the P-type substrate. Further, an N-type retrograde region is formed by implanting a high energy N-type impurity, so that a deeper, N-type second well region is formed by employing the N-type retrograde region. Further, a P-type third well region is formed in the N-type second well region, and a P-type emitter region is also formed therein. Thus, together the P-type emitter region, the N-type second well region, and the P-type third well region constitute a lateral PNP transistor. In addition, the ground voltage is maintained for the P-type third well region, which serves as a collector region.
    Type: Grant
    Filed: October 25, 1999
    Date of Patent: June 26, 2001
    Assignee: Fujitsu Limited
    Inventors: Masatomo Hasegawa, Masato Matsumiya, Satoshi Eto, Masato Takita, Toshikazu Nakamura, Ayako Kitamoto, Kuninori Kawabata, Hideki Kanou, Toru Koga, Yuki Ishii
  • Patent number: 6137146
    Abstract: A method of forming BiCMOS circuitry includes, i) conducting a first common second conductivity type implant into, a) a first substrate area to comprise a second conductivity type well for a first area first conductivity type FET, and b) a third substrate area to comprise one of a bipolar transistor second conductivity type collector or emitter region; ii) providing field oxide regions and active area regions within first, second and third areas of the substrate; iii) conducting a first common first conductivity type implant into, a) the second substrate area to comprise a first conductivity type channel stop region beneath field oxide in the second area, and b) the third substrate area to comprise the bipolar transistor base; and iv) conducting a second common second conductivity type implant into, a) at least one of the first or the second substrate areas to comprise at least one of a source/drain implant or a graded junction implant for at least one of the first or second conductivity type FETs, and b) the
    Type: Grant
    Filed: May 5, 1998
    Date of Patent: October 24, 2000
    Assignee: Micron Technology, Inc.
    Inventor: Monte Manning
  • Patent number: 5994740
    Abstract: An n.sup.- -type silicon active layer having a thickness of 6 .mu.m or less is formed on a silicon substrate via a silicon oxide film. An npn bipolar transistor with a low withstand voltage and an IGBT with a high withstand voltage are formed in the active layer. The two devices are insulated and isolated from each other through a trench. The bipolar transistor has an n-type well layer formed in the surface of the active layer. A p-type well layer is formed in the surface of the n-type well layer. The thickness of the n-type well layer under the p-type well layer is set to be 1 .mu.m or more. A first n.sup.+ -type diffusion layer is formed in the surface of the n-type well layer. A p.sup.+ -type diffusion layer and a second n.sup.+ -type diffusion layer are formed in the surface of the p-type well layer. The n-type well layer and the first n.sup.+ -type diffusion layer serve as a collector region. The p-type well layer and the p.sup.+ -type diffusion layer serve as a base region. The second n.sup.
    Type: Grant
    Filed: November 17, 1997
    Date of Patent: November 30, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akio Nakagawa, Yoshihiro Yamaguchi, Tomoko Matsudai
  • Patent number: 5952705
    Abstract: A semiconductor, where a region is introduced into a semiconductor substrate and, together with this substrate, forms a p-n junction. Provision is made in the vicinity of the space charge region being formed for a covering electrode and a heavily doped region. The covering electrode is coupled to a voltage divider, through which the potential of the covering electrode is adjusted with temperature compensation.
    Type: Grant
    Filed: January 9, 1998
    Date of Patent: September 14, 1999
    Assignee: Robert Bosch GmbH
    Inventors: Hartmut Michel, Christian Pluntke, Alfred Goerlach
  • Patent number: 5942783
    Abstract: A semiconductor circuit includes a semiconductor layer having a surface and a monolithic output stage formed in the semiconductor layer. The monolithic output stage extends to the surface of the semiconductor layer and has a periphery within the semiconductor layer, an output terminal, and a supply terminal. A barrier well is formed in the semiconductor layer and adjacent to at least a portion of the periphery of the monolithic output stage. The barrier well extends to the surface of the semiconductor layer and has a first conductivity. A diode having first and second diode regions is disposed in the semiconductor layer. The first diode region is coupled to the supply terminal. The diode is operable to prevent current flow from the barrier well to the supply terminal when the voltage between the supply and output terminals has a first polarity.
    Type: Grant
    Filed: January 31, 1996
    Date of Patent: August 24, 1999
    Assignee: STMicroelectronics, S.r.l.
    Inventors: Davide Brambilla, Edoardo Botti, Paolo Ferrari
  • Patent number: 5929506
    Abstract: A vertical PNP transistor (11) and method for making it includes forming an N- region (19) in a P substrate (12), and forming an N+ region (26) in the substrate (12) laterally surrounding and partially extending into the N- region (19). A P region (30) is formed above the N- region (19), bounded laterally by the N+ region (26) to be horizontally and vertically isolated from the substrate (12) by the N- and N+ regions (19 and 26). A layer of semiconductor material (32) is formed overall, and an N well (35) and a surrounding P well (36) are formed, each extending to the P region (30). An isolating N+ well (38) is formed surrounding the P well (36), extending to the buried N+ region (26). A P emitter region (40) and an N base contact region (41) are formed at a surface of the N well (35), and a P collector contact region (44) is formed at a surface of the P well (36).
    Type: Grant
    Filed: September 25, 1997
    Date of Patent: July 27, 1999
    Assignee: Texas Instrument Incorporated
    Inventors: Louis N. Hutter, Jeffrey P. Smith
  • Patent number: 5896313
    Abstract: An SRAM memory cell is provided in which a pair of cross-coupled n-type MOS pull-down transistors are coupled to respective parasitically formed bipolar pull-up transistors. The memory cell is formed within a semiconductor layer which extends over a buried layer. The bipolar transistors are formed parasitically from the buried layer and the semiconductor layer used to form the pull-down transistors. The bases of the bipolar transistors may also be dynamically controlled. An SRAM memory array having a plurality of such memory cells and a computer system incorporating the SRAM memory array are also provided.
    Type: Grant
    Filed: June 2, 1997
    Date of Patent: April 20, 1999
    Assignee: Micron Technology, Inc.
    Inventors: David A. Kao, Fawad Ahmed
  • Patent number: 5892268
    Abstract: A semiconductor device includes a power transistor group and a signal circuit on the same substrate. The substrate is grounded at an isolation region at an end of the substrate adjacent to the power transistor group so that the grounded portion of the substrate is distant from the signal circuit.
    Type: Grant
    Filed: August 14, 1997
    Date of Patent: April 6, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takahiro Yashita, Keisuke Kawakita, Hideki Miyake
  • Patent number: 5889315
    Abstract: Integrated circuits suitable for high-performance applications, especially mixed signal products that have analog and digital sections, are fabricatable from a semiconductor structure having two levels of buried regions. In a typical embodiment lower buried regions of opposite conductivity types are situated along a lower semiconductor interface between a semiconductive substrate and an overlying lower semiconductive layer. Upper buried regions of opposite conductivity type are similarly situated along an upper semiconductor interface between the lower semiconductive layer and an overlying upper semiconductive layer. The upper semiconductive layer contains P-type and N-type device regions in which transistor zones are situated. The semiconductor structure is normally configured so that at least one of each of the P-type and N-type device regions is electrically isolated from the substrate. Complementary bipolar transistors can be integrated with complementary field-effect transistors in the structure.
    Type: Grant
    Filed: February 23, 1995
    Date of Patent: March 30, 1999
    Assignee: National Semiconductor Corporation
    Inventors: Douglas R. Farrenkopf, Richard B. Merrill, Samar Saha, Kevin E. Brehmer, Kamesh Gadepally, Philip J. Cacharelis
  • Patent number: 5847440
    Abstract: An n-type epitaxial layer is formed on a main surface of a p-type silicon substrate. An n-type buried diffusion layer is formed extending in both the p-type silicon substrate and the n-type epitaxial layer. An n-type diffusion layer is formed in the surface of the n-type epitaxial layer, which is disposed above the n-type buried diffusion layer. A p-type diffusion layer is formed so as to surround side ends of the n-type diffusion layer. A p-type buried diffusion layer is formed so as to have a bottom face within the n-type buried diffusion layer and have side ends thereof inside side ends of the p-type diffusion layer. A collector region of a vertical pnp bipolar transistor consists of the p-type buried diffusion layer and the p-type diffusion layer. A p-type diffusion layer, which serves as an emitter region of the pnp bipolar transistor, is formed in the surface of the n-type diffusion layer.
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: December 8, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Fumitoshi Yamamoto
  • Patent number: 5834823
    Abstract: A power transistor incorporating a constant-voltage diode maintains the breakdown voltage of the constant-voltage diode at a specified level and prevents local breakdown of an insulating film located between an A1 field plate electrode and a base region of the transistor by spacing the A1 field plate electrode located on a collector region by a distance "d" from the base region.
    Type: Grant
    Filed: June 13, 1997
    Date of Patent: November 10, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Ziro Honda
  • Patent number: 5747871
    Abstract: A bipolar transistor and a process for manufacturing thereof is disclosed. The bipolar transistor has a self-aligned base electrode in which first and second pillars are formed within first and second trenches which act as an activated region and a collector region, respectively; a conductive impurities layer of high density formed at a bottom side of the first and second trenches and at a lower portion of an isolation wall between the first and second trenches; and a sequentially formed base and emitter layer. After connection to the base layer, a base contact electrode is formed within the first trench, and a collector contact electrode is formed by implanting second conductive impurities in the second pillar.
    Type: Grant
    Filed: August 13, 1996
    Date of Patent: May 5, 1998
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Kyu-Hong Lee, Jin-Hyo Lee, Jong-Sun Lyu
  • Patent number: 5708287
    Abstract: An n.sup.- -type silicon active layer having a thickness of 6 .mu.m or less is formed on a silicon substrate via a silicon oxide film. An npn bipolar transistor with a low withstand voltage and an IGBT with a high withstand voltage are formed in the active layer. The two devices are insulated and isolated from each other through a trench. The bipolar transistor has an n-type well layer formed in the surface of the active layer. A p-type well layer is formed in the surface of the n-type well layer. The thickness of the n-type well layer under the p-type well layer is set to be 1 .mu.m or more. A first n.sup.+ -type diffusion layer is formed in the surface of the n-type well layer. A p.sup.+ -type diffusion layer and a second n.sup.+ -type diffusion layer are formed in the surface of the p-type well layer. The n-type well layer and the first n.sup.+ -type diffusion layer serve as a collector region. The p-type well layer and the p.sup.+ -type diffusion layer serve as a base region. The second n.sup.
    Type: Grant
    Filed: November 29, 1995
    Date of Patent: January 13, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akio Nakagawa, Yoshihiro Yamaguchi, Tomoko Matsudai
  • Patent number: 5629551
    Abstract: A semiconductor device includes on a semiconductor substrate an output transistor which is composed of a collector region, a first base region and a first emitter region, and a temperature detection transistor composed of the collector region, a second base region and a second emitter region. The output transistor is provided at a center of the collector region of the semiconductor substrate. A vacant region is formed on a center of the output transistor, and the temperature detection transistor is provided in the vacant region.
    Type: Grant
    Filed: July 18, 1995
    Date of Patent: May 13, 1997
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hideaki Nakura, Masami Yokozawa, Kazuhiko Tsubaki, Masasuke Yoshimura
  • Patent number: 5578862
    Abstract: By reverse biasing the PN junction formed around a semiconductor element, the semiconductor element is isolated from other elements. The PN junction around the semiconductor element is a junction between a layer surrounding the semiconductor element and a layer disposed outside the layer. Jointly with the layer constituting the semiconductor, the layer surrounding the semiconductor element forms a parasitic diode. The potential of the layer on the semiconductor element to be connected to the layer surrounding the semiconductor element is detected, and based on this potential, the voltage to be applied to the parasitic diode is controlled so as to be constant. When the voltage to be applied to the parasitic diode is lower than a threshold, the parasitic diode will be in a cutoff state.
    Type: Grant
    Filed: October 13, 1994
    Date of Patent: November 26, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Nobuo Fujii, Yosuke Mizukawa, Yasuo Mitsuhashi
  • Patent number: 5567978
    Abstract: A two masking level process for a dual buried region epitaxial architecture forms a first masking layer on a surface of a P type substrate. The first masking layer exposes first and second surface portions of the substrate for N+ and P+ buried regions. N type impurities are introduced into the substrate through the first masking layer, so as to form N+ doped regions. A second masking layer is then selectively formed on the first masking layer, such that the second masking layer masks the first aperture, but exposes a second portion of the first masking layer that both includes and surrounds the second aperture. Boron impurities are then introduced through the exposed second aperture of the first masking layer, to a P+ doping concentration.
    Type: Grant
    Filed: February 3, 1995
    Date of Patent: October 22, 1996
    Assignee: Harris Corporation
    Inventor: Lawrence G. Pearce
  • Patent number: 5565695
    Abstract: A new nonvolatile hybrid memory cell is provided. The cell is comprised of a magnetic spin transistor storage element and one or two FET isolation elements. The magnetic spin transistor stores data indefinitely while drawing zero quiescent power. The FET is operated as a voltage controlled resistor, isolating the cell with a large electrical impedance when not powered and accessing the contents of the cell with a low impedance path when addressed by an appropriate voltage select signal. The cell can be used in an array of cells in a nonvolatile random access memory.
    Type: Grant
    Filed: June 22, 1995
    Date of Patent: October 15, 1996
    Inventor: Mark B. Johnson
  • Patent number: 5545917
    Abstract: A semiconductor integrated circuit has a P-type substrate and a plurality of PN-junction isolated islands of N-type, a first one of the islands may contain a power device which during certain periods of operation causes the first island to become forward biassed and to inject electrons into the substrate. Collection of these injected charges by a second island at one side of the injecting island is reduced by a separate protective bipolar transistor formed in a third N-type island. The third island is preferably interposed between the injecting island and the islands to be protected, but may be located anywhere with respect to the injecting transistor. The emitter of the protective transistor is electrically connected to an N-type portion of the first island. The collector of the protective transistor is connected to the P-type isolation-wall portion of the substrate located between the injecting transistor and the small islands to be protected.
    Type: Grant
    Filed: May 17, 1994
    Date of Patent: August 13, 1996
    Assignee: Allegro Microsystems, Inc.
    Inventors: Roger C. Peppiette, Richard B. Cooper, Robert J. Stoddard
  • Patent number: 5514901
    Abstract: In an integrated circuit in which a first PN-junction-isolated island may momentarily become forward biased with respect to the surrounding substrate and inject unwanted charge that is collected by second islands adjacent one side of a first island, the injected charge is drawn away from the second islands and to a gatherer-collector island located at another side of the first island. The first island, gatherer-collector island and intervening substrate therebetween serve respectively as the emitter, collector, and base of a protective transistor. This transistor becomes a highly efficient collector of injected charge when the protective-transistor collector is hard wired to ground and the protective-transistor base is hard-wire connected to the substrate portion between the injecting first island and adjacent second island.
    Type: Grant
    Filed: May 17, 1994
    Date of Patent: May 7, 1996
    Assignee: Allegro Microsystems, Inc.
    Inventors: Roger C. Peppiette, Richard B. Cooper, Robert J. Stoddard
  • Patent number: 5508551
    Abstract: A transistor built on a substrate employs two collectors, an output collector and a secondary collector. The purpose of the secondary collector is to collect minority carriers at saturation and feed these minority carriers back to the input reference of a current mirror. This saturation current causes a decrease in the current through the input reference transistor and decreases the current in the output of the current mirror responsively, driving it away from saturation.
    Type: Grant
    Filed: March 2, 1994
    Date of Patent: April 16, 1996
    Assignee: Harris Corporation
    Inventor: Thomas R. DeShazo
  • Patent number: 5461252
    Abstract: A semiconductor device includes on a semiconductor substrate an output transistor which is composed of a collector region, a first base region and a first emitter region, and a temperature detection transistor composed of the collector region, a second base region and a second emitter region. The output transistor is provided at a center of the collector region of the semiconductor substrate. A vacant region is formed on a center of the output transistor, and the temperature detection transistor is provided in the vacant region.
    Type: Grant
    Filed: February 17, 1995
    Date of Patent: October 24, 1995
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hideaki Nakura, Masami Yokozawa, Kazuhiko Tsubaki, Masasuke Yoshimura
  • Patent number: 5455447
    Abstract: A vertical PNP structure for use in a merged bipolar/CMOS technology has a P+ buried layer (84) as a collector region, which is isolated from the P substrate (48) by an N- buried layer (82). The P+ buried layer (84) diffuses downwards into the N- buried layer (82) and upwards into a P- epitaxy layer (52d) and into a base region (54c). The base region (54c) is formed in the same processing step as the N well region (54b) of the PMOS transistor (42) and the collection region (54a) of the NPN transistor (40). By diffusing into the base region (54c), the width between the collector (84) and emitter (64e) is reduced. The emitter (64e) can be formed in conjunction with the source and drain regions of the PMOS transistor (42).
    Type: Grant
    Filed: September 30, 1992
    Date of Patent: October 3, 1995
    Assignee: Texas Instruments Incorporated
    Inventors: Louis N. Hutter, Joe R. Trogolo
  • Patent number: 5453713
    Abstract: An integrated circuit chip has both digital and analog circuit functions, with one or more islands for isolating the analog functions from noise caused by the digital functions. An island is defined by a surrounding heavily-doped region in the face of the chip. The voltage supplies for an analog island are isolated from the digital supply voltage for high frequencies by using resistive decoupling in series along with capacitive coupling to ground. Similarly, series resistive decoupling and capacitive coupling to ground are employed for the analog input signal lines going to the island. Analog signals generated within the island are coupled to the area outside the island on the chip face by either converting to digital in an A-to-D converter, or by a differential arrangement which accounts for differences that may exist between digital and analog supply voltages.
    Type: Grant
    Filed: May 6, 1994
    Date of Patent: September 26, 1995
    Assignee: Digital Equipment Corporation
    Inventors: Hamid Partovi, Andrew J. Barber
  • Patent number: 5444291
    Abstract: An integrated bridge device includes at least two arms, each of which is formed of a first and second diode connected transistor in series. The device is formed in an N+ substrate, which forms a positive output terminal. N- and N type epitaxial layers are formed over the substrate, and P and P+ regions are formed therein for each of the aforesaid arms. An N type region is contained within the P and P+ regions, and in turn contains a P type region forming a negative potential output terminal. Also included in the N type region are N++ regions capable of minimizing the current gain of parasitic transistors formed within the device.
    Type: Grant
    Filed: November 20, 1992
    Date of Patent: August 22, 1995
    Assignee: Consorzio per la Ricerca Sulla Microelettronica Nel Mezzogiorno
    Inventors: Mario Paparo, Natale Aiello
  • Patent number: 5432376
    Abstract: The base region of the power stage and the horizontal isolation region of the integrated control circuit or collector region of a transistor of an integrated circuit consist of portions of an epitaxial layer with a first conductivity type grown in sequence on an underlying epitaxial layer with a second conductivity type opposite the first.
    Type: Grant
    Filed: April 16, 1992
    Date of Patent: July 11, 1995
    Assignee: Consorzio per la Ricera Sulla Microelettronica Nel Mezzogiorno
    Inventor: Raffaele Zambrano
  • Patent number: 5428233
    Abstract: A voltage controlled resistive device is provided by coupling a vertical bipolar transistor (34) with a junction field effect transistor (36) through a well region 18, which functions as both a drain region for the junction field effect transistor (36), and as a collector region for the vertical bipolar transistor (34). The voltage controlled resistive device of the invention provides a means of varying the output current of the vertical bipolar transistor (34) by application of a variable voltage level to the gate region (26) of the junction field effect transistor (36). To obtain proper junction bias characteristics and a compact device size, the source region (24), the gate region (26) of the junction field effect transistor (36), and the base region (22) of the vertical bipolar transistor (34) are formed in a single well region (18) of a semiconductor substrate (10).
    Type: Grant
    Filed: April 4, 1994
    Date of Patent: June 27, 1995
    Assignee: Motorola Inc.
    Inventor: Frederick W. Walczyk
  • Patent number: 5426328
    Abstract: A process is disclosed which simultaneously forms high quality complementary bipolar transistors, relatively high voltage CMOS transistors, relatively low voltage CMOS transistors, DMOS transistors, zener diodes and thin-film resistors, or any desired combination of these, all on the same integrated circuit chip. The process uses a small number of masking steps, forms high performance transistor structures, and results in a high yield of functioning die. Isolation structures, bipolar transistor structures, CMOS transistor structures, DMOS transistor structures, zener diode structures, and thin-film resistor structures are also disclosed.
    Type: Grant
    Filed: April 11, 1994
    Date of Patent: June 20, 1995
    Assignee: Siliconix incorporated
    Inventors: Hamza Yilmaz, Richard K. Williams, Michael E. Cornell, Jun W. Chen
  • Patent number: 5409845
    Abstract: Bipolar transistors and MOS transistors on a single semiconductor substrate involves depositing a single layer of polysilicon on a substrate, including complementary transistors of either or both types, and a method for fabricating same. The devices are made by depositing a single layer of polysilicon on a substrate and etching narrow slots in the form of rings around every bipolar emitter area, which slots are thereafter filled with an insulating oxide. Then, emitters and extrinsic base regions are formed. The emitters are self-aligned to the extrinsic base regions. An optional cladding procedure produces a surface layer of a silicide compound, a low resistance conductor. The resulting structure yields a high-performance device in which the size constraints are at a minimum and contact regions may be made at the top surface of the device.
    Type: Grant
    Filed: September 10, 1993
    Date of Patent: April 25, 1995
    Assignee: Analog Devices, Inc.
    Inventors: Derek W. Robinson, William A. Krieger, Andre M. Martinez, Marion R. McDevitt
  • Patent number: 5406112
    Abstract: A method for producing a semiconductor device includes a step of patterning a surface of a semiconductor substrate of first conductivity-type, a step of injecting impurity ion of second conductivity-type, a step of forming a buried well by subjecting the injected substrate to a thermal treatment, a step of forming a semiconductor crystal layer of the second conductivity-type on the substate surface, and a step of forming semiconductor elements. A semiconductor device and a longitudinal transistor produced by the method are also disclosed. In the method, after the step of forming the semiconductor crystal layer, the impurity concentration of the buried well is controlled to be nearly the same as that of the semiconductor crystal layer. According to the present invention, a semiconductor crystal layer of reverse conductivity-type to that of the substrate can be formed on the substrate in different thickness at different regions.
    Type: Grant
    Filed: September 2, 1994
    Date of Patent: April 11, 1995
    Assignee: Rohm, Co., Ltd.
    Inventor: Hisashi Sakaue
  • Patent number: 5376816
    Abstract: Disclosed herein is a Bi-CMOS IC which includes a semiconductor substrate of one conductivity type, a semiconductor layer of an opposite conductivity type formed on the substrate, a buried region of the opposite conductivity type formed between a first part of the semiconductor layer and the substrate and elongated under a second part of the semiconductor layer to form an elongated buried portion, a bipolar transistor formed in the first part by using the first part as a collector region thereof, a semiconductor region of the one conductivity type formed in the second part in contact with the elongated buried portion separately from the substrate, and an insulated gate transistor formed in the semiconductor region.
    Type: Grant
    Filed: June 23, 1993
    Date of Patent: December 27, 1994
    Assignee: NEC Corporation
    Inventors: Tadashi Nishigoori, Kiyotaka Imai
  • Patent number: 5355015
    Abstract: A lateral pnp transistor for use in programmable logic arrays. The lateral pnp has a layer of oxide disposed between a polysilicon layer and the base along the base width. The oxide layer prevents diffusion of the N+ dopant contained in the polysilicon layer into the N- base region. The base region thus remains N- and the resulting transistor has improved breakdown voltage characteristics while retaining the speed advantages of polysilicon contact layers. The lateral pnp transistor is manufactured by a method which requires minimal deviation from other methods used to manufacture lateral pnp transistors.
    Type: Grant
    Filed: November 27, 1991
    Date of Patent: October 11, 1994
    Assignee: National Semiconductor Corporation
    Inventors: Brian McFarlane, Frank Marazita, John E. Readdie
  • Patent number: 5349231
    Abstract: A method and apparatus are provided for bidirectional current conduction between first and second nodes of an electronic circuit. A first substantially constant current is conducted through a first current mirror pair of transistors coupled between the first and second nodes, in a first direction away from the first node toward the second node, in response to the first node having a voltage higher than the second node. A second substantially constant current is conducted through a second current mirror pair of transistors coupled between the first and second nodes, in a second direction away from the second node toward the first node, in response to the first node having a voltage lower than the second node.
    Type: Grant
    Filed: June 18, 1993
    Date of Patent: September 20, 1994
    Assignee: Texas Instruments Incorporated
    Inventor: Fernando D. Carvajal
  • Patent number: 5347156
    Abstract: A lateral transistor includes a semiconductor substrate, a buried layer formed on the semiconductor substrate, an epitaxial layer formed on the buried layer in such a manner that the epitaxial layer is a p-type or n-type (first conductivity-type), a diffusion zone having a second conductivity-type opposite to the first conductivity-type and including an emitter zone and collector zone formed on the epitaxial layer, and a base zone. The base zone includes an epitaxial layer interposed between the emitter zone and the collector zone. The collector zone is formed within a well zone in such a manner that the well zone has the same type conductivity as the collector zone and a lower concentration than the collector zone.
    Type: Grant
    Filed: June 18, 1992
    Date of Patent: September 13, 1994
    Assignee: Rohm Co., Ltd.
    Inventor: Hisashi Sakaue
  • Patent number: 5336911
    Abstract: A Bi-MOS semiconductor device of the type having a bipolar device and a plurality of MOS devices formed on a principal surface of a semiconductor aubstrate and a method of producing the same. The device includes a plurality of element isolation regions each thereof being composed of a first semiconductor region formed in the semiconductor substrate and having the same type of conductivity as the semiconductor substrate, and a thick insulation layer formed on the first semiconductor region, and at least one of an emitter electrode and a collector electrode formed in the bipolar device, gate electrodes formed in the MBS devices, a low-resistivity polycrystalline layer formed by a buried contact from one of the MOS devices and a high-resistivity portion formed by a high resistivity polycrystalline silicon layer connected to the low-resistivty polycrystalline silicon layer are formed from a polycrystalline silicon layer formed by the same layer formation.
    Type: Grant
    Filed: November 12, 1992
    Date of Patent: August 9, 1994
    Assignee: Seiko Epson Corporation
    Inventor: Tomoyuki Furuhata
  • Patent number: 5328858
    Abstract: A silicon oxide film is formed at a surface of a silicon substrate of a first conductive type, and then patterned to have an opening. PSG is deposited on the silicon substrate having the insulating film thereon, and then etched to leave the PSG only on a side wall of the opening. An impurity is implanted to the silicon substrate through the opening, and then thermal treatment is effected.
    Type: Grant
    Filed: October 5, 1992
    Date of Patent: July 12, 1994
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Satoshi Hikida
  • Patent number: 5319234
    Abstract: There is disclosed a C-BiCMOS semiconductor device in which a base electrode (300) of an NPN bipolar transistor and a drain electrode (360) of a PMOS transistor are formed of the same polycrystalline semiconductor, in which a base electrode (310) of a PNP bipolar transistor and a drain electrode (350) of an NMOS transistor are formed of the same polycrystalline semiconductor, and in which a source electrode (530) of the PMOS transistor and a source electrode (520) of the NMOS transistor are formed of aluminium wiring. The C-BiCMOS semiconductor device achieves preferable electric conductivity in the source electrodes, size reduction in the drain electrodes, and simplified process steps in the formation of the base electrodes of the bipolar transistors, so that the size of the devices is reduced in simple process steps without deterioration of the electric conductivity.
    Type: Grant
    Filed: July 22, 1992
    Date of Patent: June 7, 1994
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kimiharu Uga, Hiroki Honda, Masahiro Ishida, Yoshiyuki Ishigaki
  • Patent number: 5300805
    Abstract: A bias structure for an integrated circuit including first and second transistors having emitter terminals coupled respectively to the supply and to a terminal of a resistor whose potential, under certain operating conditions of the circuit, exceeds the supply voltage; base terminals connected to each other and to a current source; and collector terminals connected electrically (12) to an epitaxial tub housing the resistor. A resistor is preferably provided between the two collectors, so that, when the potential of the terminal of the resistor exceeds the supply voltage, the second transistor saturates and maintains the epitaxial tub of the resistor at a potential close to that of the resistor terminal, thus preventing the parasitic diode formed between the resistor and the epitaxial tub from being switched on.
    Type: Grant
    Filed: June 29, 1993
    Date of Patent: April 5, 1994
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Marco Demicheli, Alberto Gola
  • Patent number: 5298787
    Abstract: A permeable base transistor (30) including a metal base layer (34) embedded in a semiconductor crystal (32) to separate collector (38) and emitter (40) regions and form a Schottky barrier with each is diclosed. The metal base layer has at least one opening (37) through which the crystal semiconductor (32) joins the collector (38) and emitter (40) regions. Ohmic contacts (42,44) are made to the emitter (38) and collector (40) regions. The width of all openings (37) in the base layer (34) is of the order of the zero bias depletion width corresponding to the carrier concentration in the opening. The thickness of the metal layer (34) is in the order of 10% of this zero bias depletion width. As a result, a potential barrier in each opening limits current flow over the lower portion of the bias range.
    Type: Grant
    Filed: April 1, 1991
    Date of Patent: March 29, 1994
    Assignee: Massachusetts Institute of Technology
    Inventors: Carl O. Bozler, Gary D. Alley, William T. Lindley, R. Allen Murphy
  • Patent number: 5296731
    Abstract: A semiconductor integrated circuit device according to the present invention includes a semiconductor layer of a first conductivity type having a high concentration of impurity atoms which layer is formed in or on predetermined locations of a semiconductor substrate with the first conductivity type which locations requires a resistance to alpha rays. The device of the present invention can decrease the amount of the electron collection to a semiconductor layer of a second conductivity type having a high concentration of impurity atoms which layer is separated from the semiconductor layer of the first conductivity type having a high concentration of impurity atoms. Therefore, the semiconductor integrated circuit device of the present invention can have enhanced resistance to alpha rays without capacitances being increased and maintain a fast speed of circuit operation.
    Type: Grant
    Filed: September 30, 1992
    Date of Patent: March 22, 1994
    Assignee: NEC Corporation
    Inventor: Takenori Morikawa
  • Patent number: 5286986
    Abstract: In a semiconductor device, a charge transfer device, a bipolar transistor, and a MOSFET are formed on a single chip, and the peripheral portion of the charge transfer device is surrounded by an N.sup.+ -type region. Since the charge transfer device block is surrounded by the N.sup.+ -type region and the N.sup.+ -type buried layer, leaked charge of clocks from the charge transfer device is absorbed by the N.sup.+ -type region and the N.sup.+ -type buried layer.
    Type: Grant
    Filed: February 18, 1992
    Date of Patent: February 15, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuo Kihara, Minoru Taguchi
  • Patent number: 5245209
    Abstract: The impurity concentration of an n.sup.+ buried layer 51a in the region for forming a p channel MOS transistor 23 is higher than the impurity concentration of an n.sup.+ buried layer 3a in the region for forming an npn bipolar transistor 21. N.sup.+ buried layers 3a and 51a are formed on a p type silicon substrate 1. An n.sup.- well region 10 is formed as a region for forming npn bipolar transistor 21 on n.sup.+ buried layer 3a. An n well region 12 is formed as a region for forming p channel MOS transistor 23 on n.sup.+ buried layer 51a. While the performance of npn bipolar transistor 21 is maintained, the performance of a CMOS transistor formed of an n channel MOS transistor 22 and p channel MOS transistor 23 is improved. In a Bi-CMOS semiconductor device, the performance of a bipolar transistor portion is maintained, while preventing the formation of a punch through and improving the latch up tolerance of a CMOS transistor portion.
    Type: Grant
    Filed: November 27, 1991
    Date of Patent: September 14, 1993
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Yoshiyuki Ishigaki