Combined With Bipolar Transistor Patents (Class 257/370)
  • Patent number: 5949128
    Abstract: A bipolar transistor with MOS-controlled protection for a reverse-biased emitter-base junction is disclosed. A bipolar transistor and a MOS transistor are configured with the drain and the gate electrically coupled to the emitter, and the source and body electrically coupled to the base. A reverse-bias at the emitter-base junction, which is less than a breakdown voltage for the emitter-base junction, activates the MOS transistor which substantially reduces the resistance between the emitter and the base. Preferably, a first semiconductor region provides both the drain and the emitter, and a second semiconductor region provides both the body and the base, for reduced surface area on an integrated circuit chip.
    Type: Grant
    Filed: March 30, 1998
    Date of Patent: September 7, 1999
    Assignee: Lucent Technologies Inc.
    Inventor: Muhammed Ayman Shibib
  • Patent number: 5936288
    Abstract: Anode and cathode regions at a principal surface of a semiconductor substrate have the same characteristics as source and drain regions of a P type MOS transistor. A cathode region is superposed partially on the anode region at the principal surface of the semiconductor substrate, the cathode region having the same characteristics as source and drain regions of an N type MOS transistor. The cathode and anode regions form a Zener diode. The Zener diode may be short-circuited by a large current flow, i.e., zapping, or used as a voltage regulator.
    Type: Grant
    Filed: December 9, 1997
    Date of Patent: August 10, 1999
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Kyoei Sangyo Co. Ltd.
    Inventors: Kazuhito Tsuchida, Kouji Kashimoto, Satoshi Kadono
  • Patent number: 5917222
    Abstract: A process flow which can be used to fabricate a high frequency bipolar transistor 147, a power transistor 146, and non-power MOS devices on a single substrate while maintaining superior performance. The process flow forms an initial high-voltage tank 170 in substrate 150. A thin epitaxial layer 156 is formed on the substrate which overlies the initial high voltage tank and Diffusion Under Film, DUF, region 154. The high voltage tank is extended through the epitaxial layer and power transistor 146 is formed in the high voltage tank and high frequency bipolar transistor 147 is formed in the epitaxial layer using the DUF region as a deep collector. Other types of low voltage devices 139 and 140 and mid voltage devices 141-145 and 148-149 are formed unaffected by the presence of epitaxial layer 156. A single chip transmitter 400 and a single chip receiver 410 is fabricated with high frequency transistors and power devices.
    Type: Grant
    Filed: February 20, 1998
    Date of Patent: June 29, 1999
    Assignee: Texas Instruments Incorporated
    Inventors: Michael C. Smayling, Ronald N. Parker, Manuel L. Torreno, Jr., deceased
  • Patent number: 5910676
    Abstract: A BiCMOS structure and a method for making the same is disclosed, where the dielectric layer between the emitter electrode and the base region is formed of a deposited dielectric. After definition of the bipolar and MOS moat regions, a layer of polysilicon is deposited thereover, and removed from the bipolar region. The base implant is performed either prior to or after the etch of the polysilicon layer. A layer of TEOS oxide is formed thereover and is etched to remain in portions of the bipolar region, with an emitter contact formed therethrough and a portion of the bipolar region exposed at which the extrinsic base is formed. An alternative embodiment of the invention includes scaling the emitter contact by forming sidewall oxide filaments therewithin. A second layer of polysilicon is disposed thereover to form the emitter electrode, and to merge with the first layer to form the gates of the MOS transistors.
    Type: Grant
    Filed: December 10, 1993
    Date of Patent: June 8, 1999
    Assignee: Texas Instruments Incorporated
    Inventors: Scott H. Prengle, Robert H. Eklund
  • Patent number: 5910675
    Abstract: A semiconductor device includes a metal terminal provided on a semiconductor substrate and a protection element. The protection element includes an insulated gate field-effect transistor. The transistor has a first diffusion layer of a reverse conductive-type formed on one conductive type region of the semiconductor substrate and connected to the metal terminal, as its source. The transistor also includes a second diffusion layer of a reverse conductive-type connected to an electrode wire having a constant electric potential, as its source, and has a gate electrode connected to the electrode wire. A lateral bipolar transistor includes a third diffusion layer of a reverse conductive-type formed with a constant spaced distance with respect to the second diffusion layer and connected to the metal terminal, as its collector, and also has the second diffusion layer as its emitter, and furthermore has the one conductive-type region as its base.
    Type: Grant
    Filed: December 11, 1996
    Date of Patent: June 8, 1999
    Assignee: NEC Corporation
    Inventors: Yoko Horiguchi, Kaoru Narita, Takeo Fujii
  • Patent number: 5910674
    Abstract: A semiconductor integrated circuit device wherein a semiconductor layer of a second conductivity type is formed at a region excluding a region where a semiconductor element of the second conductivity type is formed, or at a region having an adequate area in a semiconductor substrate of a first conductivity type, a semiconductor element of the first conductivity type is formed in the semiconductor layer of the second conductivity type, and a semiconductor element of the second conductivity type is formed at the region where the semiconductor layer of the second conductivity type is not formed, and a method of fabricating the device.
    Type: Grant
    Filed: May 16, 1997
    Date of Patent: June 8, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Yoshio Kasai
  • Patent number: 5899714
    Abstract: Integrated circuits suitable for high-performance applications, especially mixed signal products that have analog and digital sections, are fabricated from a semiconductor structure in which lower buried regions of opposite conductivity types are situated along a lower semiconductor interface between a semiconductive substrate and an overlying lower semiconductive layer. An upper buried region of a selected conductivity type is situated along an upper semiconductor interface between the lower semiconductive layer and an overlying upper semiconductive layer. Another upper buried region of opposite conductivity type to the first-mentioned upper buried region is preferably situated along the upper semiconductor interface. The upper semiconductive layer contains P-type and N-type device regions in which transistor zones are situated. The semiconductor structure is configured so that at least one of each of the P-type and N-type device regions is electrically isolated from the substrate.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: May 4, 1999
    Assignee: National Semiconductor Corporation
    Inventors: Douglas R. Farrenkopf, Richard B. Merrill, Samar Saha, Kevin E. Brehmer, Kamesh Gadepally, Philip J. Cacharelis
  • Patent number: 5892263
    Abstract: A complementary metal-oxide-semiconductor device having a semiconductor region of an n conductivity type connected to a high-potential power supply, in which a p-channel MOSFET is formed, and a semiconductor region of a p conductivity type connected to a low-potential power supply, in which an n-channel MOSFET is formed, characterized in that at least one of the following two states, that is, one state in which a source of said p-channel MOSFET is connected to a lower high-potential power supply having a potential lower than that of said high-potential power supply and another state in which a source of said n-channel MOSFET is connected to a higher low-potential power supply having a potential higher than that of said low-potential power supply is realized.
    Type: Grant
    Filed: January 16, 1997
    Date of Patent: April 6, 1999
    Assignee: NEC Corporation
    Inventor: Tsuyoshi Tachiyama
  • Patent number: 5886387
    Abstract: Disclosed are a semiconductor integrated circuit device capable of including both a bipolar transistor and a MOS transistor while maintaining high performances of then both and a method of fabricating the device. On a p-type silicon substrate a plurality of n.sup.+ -type regions are formed below the buried collector region of a bipolar transistor and the n-type well region of a MOS transistor. A plurality of p-type regions are formed below the isolation region of the bipolar transistor and the p-type well region of the MOS transistor. An epitaxial layer is formed on the substrate including these n.sup.+ -type and p-type regions. This epitaxial layer forms element region layers having a bipolar transistor region and a MOS transistor region. The thickness of the layer of the bipolar transistor region is smaller than that of the layer of the MOS transistor region.
    Type: Grant
    Filed: September 23, 1996
    Date of Patent: March 23, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masahito Nishigohri, Kazunari Ishimaru
  • Patent number: 5880002
    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: December 6, 1996
    Date of Patent: March 9, 1999
    Assignee: Texas Instruments Incorporated
    Inventors: Louis N. Hutter, Jeffrey P. Smith
  • Patent number: 5856218
    Abstract: In an NPN bipolar transistor having a special structure in which each impurity region is formed by ion implantation, a width of a base region is significantly reduced, and therefore, current amplification factor hfe is increased, resulting in improvement in performance thereof. Furthermore, a Bi-CMOS transistor can be manufactured using a CMOS process. The use of the bipolar transistor having a special structure for a driving circuit allows implementation of a driving circuit having large driving force with slight increase in cost.
    Type: Grant
    Filed: May 5, 1997
    Date of Patent: January 5, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Atsushi Kinoshita, Tomohisa Wada
  • Patent number: 5856695
    Abstract: A BiCMOS process which provides both low voltage (digital) and high voltage (analog) CMOS devices. The high voltage NMOS devices have a compensated drain formed by the NPN and PNP base implants. The PNP base plus the high voltage NMOS drain carrier concentrations are both optimized by adjustment of the two variables N base implant dose and P base implant dose; this determines the NPN base carrier concentration which turns out to provide good NPN characteristics. Low voltage NMOS source and drain implants employ a higher dose and may also be used for the high voltage NMOS source. The NPN emitter doping may also be used for a contact to the high voltage NMOS drain contact.
    Type: Grant
    Filed: July 20, 1992
    Date of Patent: January 5, 1999
    Assignee: Harris Corporation
    Inventors: Akira Ito, Michael David Church
  • Patent number: 5856697
    Abstract: A new method of isolating a polysilicon emitter from the base region of a bipolar transistor, trenching the polysilicon emitter into the semiconductor substrate, and maintaining a consistent base width of a bipolar transistor independent of variations in emitter mask thicknesses is disclosed. The polysilicon emitter isolation provides for better electrical breakdown characteristics between the emitter and the base by protecting the dielectric layer between the polysilicon emitter and base regions from defects and contamination associated with the BiCMOS manufacturing environment. The polysilicon emitter is trenched into the semiconductor substrate in order to reduce transistor operation problems associated with hot electron injection. Consistent base widths improve transistor performance uniformity thereby improving manufacturability and reliability.
    Type: Grant
    Filed: July 14, 1997
    Date of Patent: January 5, 1999
    Assignee: Intel Corporation
    Inventors: Stephen Chambers, Brian J. Brown, Chan-Hong Chern, Robert Chau, Leopoldo D. Yau
  • Patent number: 5844280
    Abstract: A protection device for protecting a semiconductor circuit from positive and negative overvoltage such as static electrical discharges. A p-type substrate is provided having a pair of spaced apart n-type regions formed therein. Each of the spaced apart n-type regions has a p.sup.+ region and an n.sup.+ region formed therein. Each of the spaced apart n-type regions also includes an n.sup.+ drain tap which has a portion in contact with the substrate. The n.sup.+ region and one p.sup.+ region of one of the spaced apart n-type regions are connected to a terminal of a semiconductor circuit. The n.sup.+ region and p.sup.+ regions of the other n-type region are connected to a power voltage of the semiconductor device. A insulated gate is formed on a p-type semiconductor substrate, and is in contact with both n+ drain taps. The gate is grounded. The bilateral protection device of the present invention protects the semiconductor circuit against positive and negative overvoltages.
    Type: Grant
    Filed: December 30, 1996
    Date of Patent: December 1, 1998
    Assignee: Samsung Electronics, Co., Ltd.
    Inventor: Dae-Kyu Kim
  • Patent number: 5844268
    Abstract: A select MOS transistor and a data storage MOS transistor are formed in an element region. The transistor has floating-gate electrodes. The floating-gate electrodes are spaced apart above the element region and connected to each other above a field region. Only a tunnel insulating film much thinner than a gate insulating film of the transistor is placed between the floating-gate electrode and a drain region. Only the gate insulating film much thinner than the gate insulating film of the transistor is placed between the floating-gate electrode and the channel region of the transistor. In the element region, the shape of a control electrode is the same as that of the floating-gate electrodes.
    Type: Grant
    Filed: November 1, 1996
    Date of Patent: December 1, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Junichiro Noda, Daisuke Tohyama
  • Patent number: 5840603
    Abstract: A first photoresist layer has opening portions in a region where an n-channel MOS transistor should be formed and in a region where a collector leading region should be formed. Then, phosphorous is implanted with taking the first photoresist layer as a mask. The first photoresist layer is then removed and a second photoresist layer is formed. The second photoresist layer has opening portions in a region where an emitter region should be formed and in the region where the collector leading region should be formed. Phosphorous is implanted with taking the second photoresist layer as a mask to form an n-type selective diffusion region in a region below the region where the emitter region should be formed and in the region where the collector leading region should be formed. Then, the second photoresist layer is removed. A polycrystalline silicon layer is formed over the entire surface and arsenic is implanted therein to make it n-type.
    Type: Grant
    Filed: August 20, 1997
    Date of Patent: November 24, 1998
    Assignee: NEC Corporation
    Inventor: Kayoko Sakamoto
  • Patent number: 5838048
    Abstract: A silicon oxide film and a polysilicon film are formed on a silicon substrate and are selectively etched to form a contact hole in a region where an emitter is to be formed. A polysilicon film is laid on the substrate and two polysilicon films are patterned to form an emitter electrode and a gate electrode made of the two polysilicon films which are doped with arsenic. The arsenic is diffused from the polysilicon films of the emitter electrode into the silicon substrate to form an N.sup.+ emitter layer which has a high concentration and is shallow. Consequently, the contamination of a gate insulator film can be prevented from occurring and a bipolar transistor having high performance, for example, a high current amplification factor or the like can be formed.
    Type: Grant
    Filed: August 20, 1997
    Date of Patent: November 17, 1998
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takehiro Hirai, Masahiro Nakatani, Mitsuo Tanaka, Akihiro Kanda
  • Patent number: 5828110
    Abstract: An arrangement that prevents triggering of latchup in internal circuits by input/output buffers on an integrated circuit chip provides a space surrounding each active device connected to a bond pad. A ring well surrounds the space and separates the active device from the internal circuits of the chip. The ring well serves as a collector to prevent triggering latchup by the active device of the internal circuits located outside the ring well.
    Type: Grant
    Filed: December 18, 1996
    Date of Patent: October 27, 1998
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Donald L. Wollesen
  • Patent number: 5828109
    Abstract: In a semi-conductor integrated circuit device, electric charges which relate to latch-up phenomenon generation are absorbed effectively, and thereby generation of the latch-up phenomenon is prevented. Low-concentration impurity diffusion layers of I/O transistor within I/O transistor region are electrically connected to high-concentration impurity diffusion layers with different conductive characteristics each. Furthermore, low-concentration impurity diffusion layers of internal circuit transistors within internal circuit transistor region are electrically connected to high-concentration impurity diffusion layers with different conductive characteristics each, or are brought into directly contact therewith, thus electrically connecting thereto. For this reason, it causes an observed area of the low-concentration impurity diffusion layer of the transistors to enlarge, thus absorbing the electric charges causing the latch-up phenomenon generation.
    Type: Grant
    Filed: March 27, 1997
    Date of Patent: October 27, 1998
    Assignee: NEC Corporation
    Inventor: Hitoshi Okamoto
  • Patent number: 5828263
    Abstract: A temperature sensor contains a bipolar transistor adjacent a cell array of a power MOSFET or IGBT. In order to detect temperature independently of a voltage drop across the power semiconductor component, a zone of the same conduction type is disposed between the cell array and a base zone. That zone is connected to a fixed bias voltage.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: October 27, 1998
    Assignee: Siemens Aktiengesellschaft
    Inventors: Josef-Matthias Gantioler, Holger Heil, Norbert Krischke
  • Patent number: 5811860
    Abstract: A merged BiCMOS device 10 having a bipolar transistor 60 and a PMOS transistor 64 formed in the same well region 18. Bipolar transistor 60 is comprised of an emitter electrode 30, base region 26, and collector region formed by well region 18. Emitter electrode 30 is separated from base region 26 by thick oxide 24. Tungsten-silicide layer 32 covers emitter electrode 30. PMOS transistor 64 comprises source/drain regions 52 and 52a, gate electrode 40, and gate oxide 36. PMOS transistor 64 may optionally comprise LDD regions 44. Source/drain region 52a is in contact with base region 26. If desired, the emitter electrode 30 and gate electrode 40 may be silicided.
    Type: Grant
    Filed: April 28, 1995
    Date of Patent: September 22, 1998
    Assignee: Texas Instruments Incorporated
    Inventor: Robert Howard Eklund
  • Patent number: 5801418
    Abstract: Level shift devices are formed in the high voltage termination region of an integrated circuit. The level shift devices provide a connection between the higher voltage, floating circuit and a ground referenced lower voltage circuit. The structure of the level shift devices eliminates the need for a high voltage connector to cross over the low voltage connector.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: September 1, 1998
    Assignee: International Rectifier Corporation
    Inventor: Niraj Ranjan
  • Patent number: 5798552
    Abstract: A method and an apparatus for forming a transistor suitable for a high voltage circuit. In one embodiment, the transistor is formed without adding any steps to an existing state-of-the-art CMOS process. A well is implanted into a portion of a substrate such that the well has a higher doping concentration than the substrate. A first diffusion region is then implanted into the substrate such that at least a portion of the first diffusion is disposed within the well. In addition, a second diffusion is implanted into the substrate separated from the well such that the second diffusion region is disposed entirely outside the well. A channel region is disposed between the first and second regions and gate is disposed over the channel region to form the high voltage transistor. Since the second diffusion region is disposed entirely outside the well in the lower doped substrate, a higher junction breakdown voltage is realized.
    Type: Grant
    Filed: July 8, 1997
    Date of Patent: August 25, 1998
    Assignee: Intel Corporation
    Inventors: Mohsen Alavi, Tahir Ghani
  • Patent number: 5793085
    Abstract: A bipolar transistor, comprising a collector region, a base region, and an emitter region, is a type which is compatible to CMOS processes leading to the formation, on a semiconductor substrate, of N-channel and P-channel MOS transistors having respective source and drain regions. In such bipolar transistor, the collector region is a substrate diffused pocket and the base region is formed within the diffused pocket simultaneously with the source and drain regions of the P-channel MOS transistors. Further, the emitter region is incorporated, in turn, to the base region simultaneously with the source and drain regions of the N-channel MOS transistors.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: August 11, 1998
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Bruno Vajana, Emilio Ghio
  • Patent number: 5789790
    Abstract: A semiconductor device has a transistor made of a semiconductor which has a source and drain regions, a channel region, a gate insulative film, and a gate electrode. The gate electrode is connected to a part of the channel region. The channel region has the same conductivity type as that of the source and drain regions and has an impurity concentration lower than that of the source and drain regions.
    Type: Grant
    Filed: October 27, 1995
    Date of Patent: August 4, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masakazu Morishita, Shigetoshi Sugawa, Toru Koizumi
  • Patent number: 5780329
    Abstract: A bipolar transistor with a relatively deep emitter region is formed in a BICMOS device using the source/drain mask used to form the source and drain regions of MOSFETs of the device and the base region mask which would otherwise be required in any event to diffuse an emitter region of the bipolar transistor. The emitter is diffused or implanted to a depth greater than the depth to which a source and a drain region of the MOSFET are diffused. By using only the base region and source/drain region masks, and developing in sequence, each of two coatings of photoresist applied on top of one another, an access opening to the emitter region is define solely by the co-location of openings in each of the two coatings, thereby allowing the emitter region to be separately and additionally implanted. The access to the base region for the additional implication is achieved using only a few additional photo-ops and not as a result of using an additional emitter mask.
    Type: Grant
    Filed: April 3, 1997
    Date of Patent: July 14, 1998
    Assignee: Symbios, Inc.
    Inventors: Todd A. Randazzo, John J. Seliskar
  • Patent number: 5777510
    Abstract: A pull-up output driver circuit includes a field effect transistor (FET) fabricated in a well region having a first conductivity type. The well region, in turn, is surrounded by a semiconductor region having a second conductivity type. The FET has a source connected to an output pad and a drain connected to a V.sub.CC voltage supply rail. The gate of the FET and the well region are connected to a driving circuit, and the semiconductor region is connected to the V.sub.CC voltage supply rail. A lateral bipolar transistor is formed by the drain, the source and the well region, and a vertical parasitic bipolar transistor is formed by the source, the semiconductor region and the well region. The driving circuit provides a signal (or signals) to the gate and well region to control the pull-up driver circuit. The FET turns on at a relatively low threshold voltage because the lateral bipolar transistor and the FET are turned on at substantially the same time.
    Type: Grant
    Filed: February 21, 1996
    Date of Patent: July 7, 1998
    Assignee: Integrated Device Technology, Inc.
    Inventor: Chuen-Der Lien
  • Patent number: 5767551
    Abstract: A process flow which can be used to fabricate a high frequency bipolar transistor 147, a power transistor 146, and non-power MOS devices on a single substrate while maintaining superior performance. The process flow forms an initial high-voltage tank 170 in substrate 150. A thin epitaxial layer 156 is formed on the substrate which overlies the initial high voltage tank and Diffusion Under Film, DUF, region 154. The high voltage tank is extended through the epitaxial layer and power transistor 146 is formed in the high voltage tank and high frequency bipolar transistor 147 is formed in the epitaxial layer using the DUF region as a deep collector. Other types of low voltage devices 139 and 140 and mid voltage devices 141-145 and 148-149 are formed unaffected by the presence of epitaxial layer 156. A single chip transmitter 400 and a single chip receiver 410 is fabricated with high frequency transistors and power devices.
    Type: Grant
    Filed: March 4, 1997
    Date of Patent: June 16, 1998
    Assignee: Texas Instruments Incorporated
    Inventors: Michael C. Smayling, Ronald N. Parker, Manuel L. Torreno, Jr., deceased
  • Patent number: 5763920
    Abstract: A "BiCMOS" semiconductor integrated circuit, a gate oxide film 110 and a polysilicon film are grown on a semiconductor substrate, and after phosphorus is doped, the polysilicon film is patterned to form gate electrodes 112a and 112b and an emitter electrode 112c. A heat treatment is performed to form an emitter diffused region 113. Phosphorus and boron are selectively implanted with a low impurity concentration, respectively, to form a LDD N.sup.- region 114 and a LDD P.sup.- region 115. Thereafter, a side wall 116 is formed, and boron is implanted into areas B and C so as to form P.sup.+ source/drain regions 117 and a graft base region 18, respectively. Phosphorus is implanted to form N.sup.+ source/drain regions 119.
    Type: Grant
    Filed: August 7, 1997
    Date of Patent: June 9, 1998
    Assignee: NEC Corporation
    Inventor: Toshio Komuro
  • Patent number: 5760448
    Abstract: A semiconductor device having an electrostatic discharge protection device and at least one accompanying device selected from the group comprising of a N or P channel MOS transistor, CMOS, bipolar transistor and BiCMOS, in which the electrostatic discharge protection device comprises a vertical type bipolar transistor including; a semiconductor substrate; an epitaxial layer laminated on the semiconductor substrate; a buried collector of a first conductivity type which is formed of the semiconductor substrate or which is formed from the surface of the semiconductor substrate to the epitaxial layer; a base of a second conductivity type which is a lightly doped well and formed on the epitaxial layer; and an emitter of the first conductivity type and formed on the surface layer of the base of the second conductivity type; and in which the base is adapted to have impurity concentration and depth so that a punch-through is generated between the emitter and the collector of the electrostatic discharge protection dev
    Type: Grant
    Filed: November 27, 1995
    Date of Patent: June 2, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Hiroshi Maeda
  • Patent number: 5759883
    Abstract: In a method of manufacturing a semiconductor integrated circuit device composed of a bipolar transistor and metal-oxide-semiconductor (MOS) transistors, first and second gate electrode structures are formed to have polysilicon layers having no impurity implanted and to be provided on a gate oxide film. First impurity ions are implanted in self-alignment with said first gate electrode structure to form an N-channel MOS transistor. Second impurity ions are implanted in self-alignment with said second gate electrode structure to form a P-channel MOS transistor after a bipolar transistor is formed.
    Type: Grant
    Filed: November 20, 1996
    Date of Patent: June 2, 1998
    Assignee: NEC Corporation
    Inventor: Yasushi Kinoshita
  • Patent number: 5751054
    Abstract: A semiconductor structure which includes zener diodes and various combinations of MOS transistors, bipolar transistors and DMOS transistors, all fabricated on the same integrated circuit chip
    Type: Grant
    Filed: August 29, 1996
    Date of Patent: May 12, 1998
    Assignee: Siliconix incorporated
    Inventors: Hamza Yilmaz, Richard K. Williams, Michael E. Cornell, Jun Wei Chen
  • Patent number: 5744844
    Abstract: An outline of an SRAM cell is rectangular. The SRAM cell have nMOS transistors QN1 and QN3 in a nMOS region 13A being on one side of the longitudinal direction, nMOS transistors QN2 and QN4 in a nMOS region 13B being on the opposite side thereof, pMOS transistors QP1 and QP2 in a central region 12, and isolation regions 14A and 14B being between the regions 13A and 12 and between the regions 13B and 12 respectively. The pMOS transistors QP1 and QP2 are on the nMOS transistor QN1 side and on the nMOS transistor QN2 side respectively within the region 12. The direction of bit lines is perpendicular to the longitudinal direction and the word line is parallel to the longitudinal direction. The nMOS transistors QN1, QN4 and the pMOS transistor QP1 are placed on one side of the regions 13A, 13B and 12 respectively in the direction perpendicular to the longitudinal direction, whereas the nMOS transistors QN3 and QN2 and the pMOS transistor QP2 are placed on the opposite side thereof.
    Type: Grant
    Filed: November 19, 1996
    Date of Patent: April 28, 1998
    Assignee: Fujitsu Limited
    Inventor: Tsuyoshi Higuchi
  • Patent number: 5744855
    Abstract: In a bipolar transistor of a type in which metal electrodes are formed in direct contact with a p-type external base region and an n-type collector region, respectively, an external base region surrounding an outer periphery of an n-type emitter region is formed. A metal electrode is formed on the emitter region with a polycrystalline silicon layer therebetween. Thereby, formation of a buried diffusion layer can be eliminated, and thus a manufacturing cost of the bipolar transistor can be reduced while achieving a high performance of the bipolar transistor.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: April 28, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yukio Maki, Hiroki Honda
  • Patent number: 5731617
    Abstract: A semiconductor device with a reduced insulating capacitance between an emitter electrode and a base layer, and a manufacturing method thereof are disclosed. In the semiconductor device, at least first and second insulating layers are interposed between the emitter electrode and the base layer. Preferably, the first insulating layer, a semiconductor layer having insulation characteristics, and the second insulating layer are interposed between the emitter electrode and the base layer.
    Type: Grant
    Filed: January 2, 1996
    Date of Patent: March 24, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kakutaro Suda
  • Patent number: 5726486
    Abstract: A semiconductor device allowing reduction in collector resistance can be obtained without complicating manufacturing processes. In the semiconductor device, a first impurity layer of a first conductivity type having an impurity concentration higher than that of first semiconductor region is provided such that substantially all the upper portion thereof is in contact with a lower surface of a first element isolation insulating film which is formed between a base layer and a collector extraction layer As a result, the first impurity layer serves as a current path, reducing collector resistance. In addition, the first impurity layer can be easily formed by ion implantation, so that manufacturing processes will not be complicated.
    Type: Grant
    Filed: May 15, 1997
    Date of Patent: March 10, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Yukio Maki
  • Patent number: 5721445
    Abstract: An apparatus and method for providing improved latch-up immunity in a semiconductor device such as a complementary metal-oxide-semiconductor (CMOS) integrated circuit. An exemplary apparatus includes a first region of semiconductor material of a first conductivity type, a well of semiconductor material formed in the first region and having a second conductivity type opposite to the first conductivity type, a first MOS transistor formed in the well and including a source region and a drain region formed of semiconductor material of the first conductivity type, and a second MOS transistor formed in the first region and having a source region and a drain region formed of semiconductor material of the second conductivity type. A conductive material or other suitable routing means is connected between the source region of one of the first or second MOS transistors and a corresponding voltage supply input of the device.
    Type: Grant
    Filed: March 2, 1995
    Date of Patent: February 24, 1998
    Assignee: Lucent Technologies Inc.
    Inventors: Ranbir Singh, Morgan Jones Thoma
  • Patent number: 5717240
    Abstract: In one memory cell forming region of an SRAM, a field oxide film having edges straight and parallel to each other is formed. Active regions are formed sandwiching field oxide film. One word line is formed extending over field oxide film and active regions. On word line 6, gate electrodes of a driver transistor and GND lines are formed at prescribed positions. Gate electrodes of the driver transistor also serve as a gate electrode of a TFT. On gate electrodes of the driver transistor and on GND lines, polycrystalline silicon layers in which channel region and source/drain regions of the TFT are formed, are formed respectively. Consequently, a high performance SRAM which can reduce cell area and which has high reliability can be obtained.
    Type: Grant
    Filed: June 28, 1996
    Date of Patent: February 10, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hirotada Kuriyama, Masahiro Ishida
  • Patent number: 5702959
    Abstract: A process for making a vertical PNP transistor and a transistor made by the process includes providing a highly doped semiconductor substrate (10) of P conductivity type. A first lightly doped P- layer (12) is epitaxially grown on the substrate (10). An N+ type buried layer impurity (18) is introduced into a surface region of the first lightly doped layer (12) that will underlie and define an island in which the vertical transistor will be constructed. A second lightly doped P- layer (16) is epitaxially grown on the first lightly doped layer (12) and the buried layer impurity (18). An N+ type isolation impurity is diffused into the second layer to form wells to laterally enclose an island (22) of the second layer (16) above the buried layer impurity (18). An N type base impurity (28) is diffused into the island (22) region of the second layer (16), and a P type emitter impurity (30) is diffused into the base region (28).
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: December 30, 1997
    Assignee: Texas Instruments Incorporated
    Inventors: Louis N. Hutter, Jeffrey P. Smith
  • Patent number: 5691224
    Abstract: A method of manufacturing an integrated circuit having a buried layer of a low doped type of conductivity (2) and a buried layer of a highly doped type of the same conductivity (3) by masking a substrate (1) so as to define open areas on the substrate where it is desired to provide the two buried layers and doping the open areas of the substrate with a low concentration of dopants to form the low doped type of buried layer (2) is formed. Then one open area where the low doped type of buried layer (2) is formed is masked and the other open area is doped with a high concentration of dopants to form the highly doped type of buried layer (3).
    Type: Grant
    Filed: June 25, 1996
    Date of Patent: November 25, 1997
    Assignee: Motorola, Inc.
    Inventors: Juergen Foerstner, Myriam Combes, Arlette Marty-Blavier, Guy Hautekiet
  • Patent number: 5679972
    Abstract: A semiconductor BiCMOS device and method of manufacturing suitable for attaining high packing density and thereby speeding up a switching operation, wherein the device is formed to have one of a source region or a drain region of an MOS transistor be immediately adjacent a base region of a bipolar transistor so as to be electrically connected. In this manner, an electrical terminal is eliminated, thereby permitting a higher packing density.
    Type: Grant
    Filed: July 27, 1995
    Date of Patent: October 21, 1997
    Assignee: LG Semicon Co., Ltd.
    Inventor: Sung Sik Kim
  • Patent number: 5677558
    Abstract: A low dropout linear regulator utilizing a vertical PNP transistor as its pass element, integrated with CMOS circuitry. The vertical PNP transistor includes a P-well formed in a lightly doped N type substrate for its collector. An N-type region formed in the P-well is its base and a P-type region formed in the N-type region is its emitter. The emitter receives a variable input supply and the collector provides a regulated output signal to the load being driven. As the input voltage diminishes to less than a diode drop above the output voltage, the vertical PNP transistor tries to saturate and its associated parasitic NPN transistor turns on. To limit the effects of the parasitic NPN transistor and maintain a regulated output, a current limiter is connected between the input and the collector of the NPN parasitic transistor.
    Type: Grant
    Filed: July 30, 1996
    Date of Patent: October 14, 1997
    Assignee: Analog Devices, Inc.
    Inventor: Gerard F. McGlinchey
  • Patent number: 5672897
    Abstract: An improved arrangement is provided for forming a bipolar transistor on a substrate with CMOS elements. All of the transistors (i.e., the bipolar, P-MOS and N-MOS) are formed in regions having gradually decreasing impurity concentrations from the surface toward the substrate. In addition, a buried layer is provided under each of the regions of decreasing impurity concentration in which the transistors are formed. These buried layers have a significantly higher impurity concentration than the portion of the region of decreasing impurity concentration which they are respectively adjacent to. Using this arrangement, punch-through is prevented and excellent electrical operating characteristics are provided for both the bipolar transistors and the CMOS elements.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: September 30, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Atsuo Watanabe, Takahide Ikeda, Kiyoshi Tsukuda, Mitsuru Hirao, Touji Mukai, Tatsuya Kamei
  • Patent number: 5666001
    Abstract: In production of a Bi-CMOS semiconductor device, when forming a lateral PNP transistor in a bipolar section, an oxide film is deposited on this base area to prevent etching damages such as those in forming an LDD spacer for a MOS section, thus degradation of the lateral PNP bipolar transistor and drop of yield in production thereof being prevented and a high performance (low cost) Bi-CMOS LSI being realized.
    Type: Grant
    Filed: February 24, 1994
    Date of Patent: September 9, 1997
    Assignee: Siemens Aktiengesellschaft
    Inventor: Hiroyuki Miwa
  • Patent number: 5665615
    Abstract: A BiCMOS semiconductor device comprising a substrate, a vertical bipolar transistor provided on the substrate and having a first conductive base terminal electrode formed in a portion of a first semiconductor film provided on the substrate, a second conductive semiconductor terminal electrode formed in a second semiconductor film provided through an insulating layer on the first semiconductor film, the first and second conductive electrodes being disposed such that portions thereof overlap each other, and an LDD (lightly doped drain)-type MOS transistor provided on the substrate and having a gate electrode formed in a portion of said first semiconductor film and a gate side wall formed on a side wall of said gate electrode, wherein the insulating layer is caused to exist selectively in a region in which the first and second conductive electrodes are overlapped, and constitutes at least a portion of the gate side wall.
    Type: Grant
    Filed: February 13, 1996
    Date of Patent: September 9, 1997
    Assignee: Sony Corporation
    Inventor: Hiroaki Anmo
  • Patent number: 5659193
    Abstract: The present invention is provided in order to suppress a leak current at an emitter-base junction and to implement a high-speed operation of a bipolar transistor. An n.sup.+ buried layer is formed at a surface of a p.sup.- silicon substrate. An n.sup.- epitaxial growth layer and an n.sup.+ diffused layer are formed on n.sup.+ buried layer. A p.sup.+ external base region and a p.sup.- base region are formed at a surface of n.sup.- epitaxial growth layer so as to be adjacent to each other. A first interlayer insulating layer having an opening is formed on p.sup.- base region. A groove which is located under opening and extends under first interlayer insulating layer is formed at a surface of p.sup.- base region. An n.sup.+ emitter region is formed at a bottom surface of groove within p.sup.- base region. A sidewall insulating layer is formed so as to expose n.sup.+ emitter region and to cover a sidewall of opening and to come into contact with a bottom surface of first interlayer insulating layer.
    Type: Grant
    Filed: May 28, 1996
    Date of Patent: August 19, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Yoshiyuki Ishigaki
  • Patent number: 5652456
    Abstract: A BiCMOS process is provided for fabricating on the same semiconductor substrate three types of N-wells optimized respectively for (i) PMOS FETs requiring low P+/N-well capacitance; (ii) NPN bipolar transistors which do not require low collector-to-substrate capacitance and PMOS FETs which require latch-up immunity; and (iii) NPN bipolar transistors which require low collector-to-substrate capacitance.
    Type: Grant
    Filed: July 19, 1995
    Date of Patent: July 29, 1997
    Assignee: Integrated Device Technology, Inc.
    Inventor: Chuen-Der Lien
  • Patent number: 5641692
    Abstract: A method for producing a semiconductor device which decrease the number of processes at the time of producing BiCMOSLSI than the usual. Impurities are introduced into a semiconductor substrate under a second insulating film and a first electric conductive film utilizing a first insulating film and the first conductive film formed on the semiconductor substrate as masks. Therefore, it is able to perform concurrent introduction of impurities into the gate electrode, the source and the drain of the MOSFET, the base electrode of the bipolar transistor, the emitter and the collector contact of the lateral bipolar transistor, the outlet electrode of the capacitor, and the resistor, so that the number of process steps can be reduced.
    Type: Grant
    Filed: December 18, 1995
    Date of Patent: June 24, 1997
    Assignee: Sony Corporation
    Inventors: Hiroyuki Miwa, Hiroaki Anmo
  • Patent number: 5629547
    Abstract: A BiCMOS process where a base region is formed in a relatively highly doped n-type substrate region. Boron is implanted at two different energy levels to form the base region and a counter doped n region near the base collector junction to prevent impact ionization.
    Type: Grant
    Filed: November 16, 1995
    Date of Patent: May 13, 1997
    Assignee: Intel Corporation
    Inventors: Stephen T. Chambers, Richard G. Taylor
  • Patent number: 5618688
    Abstract: An N-channel JFET (60) and a method of forming the N-channel JFET (60) in a BiCMOS process. The N-channel JFET (60) is monolithically fabricated with an N-channel IGFET (70), a P-channel IGFET (75), and an NPN BJT (80) in an epitaxial layer (21). The N-channel JFET (60) is formed in an isolated N-channel JFET region (24), the P-channel IGFET (75) is formed in an isolated P-channel IGFET region (27), and the NPN BJT (80) is formed in an isolated BJT region (29). The N-channel IGFET (70) is fabricated in a P-type well (26) that is not isolated from other N-channel IGFET's in the epitaxial layer (21). Accordingly, the N-channel JFET (60), the N-channel IGFET (70), the P-channel IGFET (75), and an NPN BJT (80) are monolithically formed in the BiCMOS process.
    Type: Grant
    Filed: February 22, 1994
    Date of Patent: April 8, 1997
    Assignee: Motorola, Inc.
    Inventors: Robert H. Reuss, Frederic B. Shapiro