Complementary Bipolar Transistors Patents (Class 438/203)
  • Patent number: 6316301
    Abstract: In a logic circuit having PMOS pull-up devices and NMOS pull-down devices, the PMOS pull-up devices are sized relative to the NMOS pull-down devices according to the number of transistors that simultaneously turn on. In one embodiment, the PMOS transistor width is determined by multiplying the effective NMOS transistor width by a predetermined factor indicative of a current carrying ratio between one of the PMOS pull-up transistors and one of the NMOS pull-down transistors and dividing by the number of PMOS pull-up transistors that simultaneously turn on to charge the output node high. Where the PMOS pull-up devices are parallel-connected, the NMOS transistor width is divided by the number of NMOS transistors.
    Type: Grant
    Filed: March 8, 2000
    Date of Patent: November 13, 2001
    Assignee: Sun Microsystems, Inc.
    Inventor: Shree Kant
  • Patent number: 6306695
    Abstract: An ESD protection circuit that will prevent internal circuits of an integrated circuit is formed on a semiconductor substrate to prevent damage during extreme voltage levels from an ESD voltage source and is connected to an input/output pad. A plurality of drains of multiple MOS FET's is formed within the surface of the semiconductor substrate and are each connected to the input/output pad. A plurality of sources of the multiple MOS FET's is formed within the surface of the semiconductor substrate and are placed at a distance from the plurality of drains and are connected to a ground reference potential. Pairs of the plurality of sources are adjacent to each other. A plurality of isolation regions placed between each source of the pairs of sources and are allowed to float. The multiple MOS FET's have a plurality of parasitic bipolar junction transistors.
    Type: Grant
    Filed: September 27, 1999
    Date of Patent: October 23, 2001
    Assignee: Taiwan Semiconductor Manufacturing Company
    Inventors: Jian-Hsing Lee, Jiaw-Ren Shih, Shui-Hung Chen, Yi-Hsun Wu
  • Publication number: 20010031525
    Abstract: A BiCMOS integrated circuit is fabricated using a minimum number of wafer processing steps and yet offers the IC circuit designer five (5) different transistor types. These types include P-channel and N-channel MOS transistors and three different bipolar transistors whose emitters are all formed by a different process and all are characterized by different current gains and different breakdown voltages. A differential silicon dioxide/silicon nitride masking technique is used in the IC fabrication process wherein both P-type buried layers (PBL) and N-type buried layers (NBL) are formed in a silicon substrate using a single mask set and further wherein P-type wells and N-type wells are formed above these buried layers in an epitaxial layer, also using a single SiO2/Si3N4 differential mask set. Two of the bipolar transistor emitters are formed by out diffusion from first and second levels of polysilicon, whereas the emitter of the third bipolar transistor is formed by ion implantation doping.
    Type: Application
    Filed: June 4, 2001
    Publication date: October 18, 2001
    Applicant: Micron Technology, Inc.
    Inventors: Michael Violette, Martin Ceredig Roberts
  • Patent number: 6300669
    Abstract: A semiconductor integrated circuit device comprises a multiple-stage amplifier including a plurality of transistors. The multiple-stage amplifier has a first stage comprising a plurality of bipolar transistors each having a single emitter structure. The bipolar transistors are connected parallel to each other. The semiconductor integrated circuit device can easily be designed, is of a self-aligned structure, and has a single transistor size. The semiconductor integrated circuit device may be used as a low-noise, high-power-gain high-frequency amplifier.
    Type: Grant
    Filed: September 25, 1998
    Date of Patent: October 9, 2001
    Assignee: NEC Corporation
    Inventor: Yasushi Kinoshita
  • Patent number: 6291282
    Abstract: An embodiment of the instant invention is a method of forming a first transistor having a first gate electrode and a second transistor having a second gate electrode on a semiconductor substrate, the method comprising the steps of: forming a conductive material (step 216 of FIG. 2) insulatively disposed over the semiconductor substrate, the conductive material having a work function; and altering a portion of the conductive material (step 218 of FIG. 2) so as to change the work function of the altered conductive material, the conductive material to form the first gate electrode and the altered conductive material to form the second gate electrode. Preferably, the first transistor is an NMOS device, the second transistor is a PMOS device, and the first transistor and the second transistor form a CMOS device. The conductive material is, preferably, comprised of a conductor selected from the group consisting of: Ta, Mo, Ti and any combination thereof.
    Type: Grant
    Filed: February 8, 2000
    Date of Patent: September 18, 2001
    Assignee: Texas Instruments Incorporated
    Inventors: Glen D. Wilk, Scott R. Summerfelt
  • Patent number: 6271068
    Abstract: A method for making an improved polysilicon emitter for a bipolar transistor in a BiCMOS integrated circuit is achieved. The method uses a novel stacked undoped amorphous silicon layer and a doped polysilicon layer. The polysilicon layer is doped by ion implantation while the amorphous silicon layer remains undoped. The stacked layer is patterned to form a polysilicon emitter source over the bipolar transistor, while concurrently forming gate electrodes for the FETs. The undoped amorphous silicon layer retards the diffusion from the doped polysilicon to provide a shallower emitter junction during subsequent thermal processing. At a later step a rapid thermal anneal (RTA) is carried out in which the amorphous silicon layer provides better control of the diffused emitter depth (junction) while concurrently activating the implant dopant in the FET source/drain areas.
    Type: Grant
    Filed: January 8, 2001
    Date of Patent: August 7, 2001
    Assignee: Taiwan Semiconductor Manufacturing Company
    Inventors: Yung-Lung Hsu, Ruey-Hsin Liou
  • Patent number: 6268250
    Abstract: An efficient method for fabricating dual well type structures uses the same number of masks used in single well type structure fabrication. In a preferred embodiment, the current invention allows low voltage and high voltage n-channel transistors and low voltage and high voltage p-channel transistors to be formed in a single substrate. One mask is used for forming a diffusion well, a second mask for both forming a retrograde well and doping the well to achieve an intermediate threshold voltage in that well, and a third mask for both differentiating the gate oxides for the low voltage devices and doping the threshold voltages to achieve the final threshold voltages.
    Type: Grant
    Filed: May 14, 1999
    Date of Patent: July 31, 2001
    Assignee: Micron Technology, Inc.
    Inventor: Mark A. Helm
  • Patent number: 6245609
    Abstract: A new design for a high voltage bipolar transistor is disclosed. Instead of a buried subcollector (which would be N+ in an NPN device), a buried P+ layer is used. The presence of this P+ layer results in pinch-off between itself and the bipolar base. This allows much higher breakdown voltages to be achieved. In particular, the device will not break down at the bottom of the base-collector junction which is the weak spot for conventional devices. A process for manufacturing this device is described. A particular feature of this new process is that the N type epitaxial layer that is grown over the P+ layer is only about half the thickness of its counterpart in the conventional device. The process is fully compatible with conventional BiCMOS processes and has lower cost.
    Type: Grant
    Filed: September 27, 1999
    Date of Patent: June 12, 2001
    Assignee: Taiwan Semiconductor Manufacturing Company
    Inventors: Jun-Lin Tsai, Ruey-Hsin Liu, Jei-Feng Hwang, Kuo-Chio Liu
  • Patent number: 6245604
    Abstract: A BiCMOS integrated circuit is fabricated using a minimum number of wafer processing steps and yet offers the IC circuit designer five (5) different transistor types. These types include P-channel and N-channel MOS transistors and three different bipolar transistors whose emitters are all formed by a different process and all are characterized by different current gains and different breakdown voltages. A differential silicon dioxide/silicon nitride masking technique is used in the IC fabrication process wherein both P-type buried layers (PBL) and N-type buried layers (NBL) are formed in a silicon substrate using a single mask set and further wherein P-type wells and N-type wells are formed above these buried layers in an epitaxial layer, also using a single SiO2/Si3N4 differential mask set. Two of the bipolar transistor emitters are formed by out diffusion from first and second levels of polysilicon, whereas the emitter of the third bipolar transistor is formed by ion implantation doping.
    Type: Grant
    Filed: January 16, 1996
    Date of Patent: June 12, 2001
    Assignee: Micron Technology
    Inventors: Michael Violette, Martin Ceredig Roberts
  • Patent number: 6235588
    Abstract: The present invention relates to a method of manufacturing a MOS transistor, including the steps of delimiting, using a first resist mask N-type, drain and source implantation areas; removing the first mask and diffusing the implanted dopant; annealing, so that a thicker oxide forms above the source and drain regions than above the central gate insulation area; forming a polysilicon finger above the central gate insulation portion to form the gate of the MOS transistor; and performing a second source/drain implantation.
    Type: Grant
    Filed: March 30, 1999
    Date of Patent: May 22, 2001
    Assignee: STMicroelectronics S.A.
    Inventor: Michel Laurens
  • Patent number: 6177298
    Abstract: An ESD protection circuit (11) includes a low capacitance diode (26), a voltage divider, a trigger transistor (16), and an SCR. Reducing the capacitance associated with the diode (26) makes the ESD protection circuit particularly suitable for RF applications. To form a low capacitance diode, the parasitic junction capacitance of the diode (26) is hidden in a like-doped well; for example, an N+ cathode (54) of the diode (26) may be folded or formed partially in an N-well (53). Because the N-well (53) does not form a junction with the N+ cathode, the junction capacitance associated with the portion of the N+ well lying inside the N-well is hidden or canceled by the N-well (53), thereby reducing the overall capacitance of the diode (26).
    Type: Grant
    Filed: February 2, 1998
    Date of Patent: January 23, 2001
    Assignee: Motorola, Inc.
    Inventor: John H. Quigley
  • Patent number: 6140170
    Abstract: Complementary vertical bipolar and DMOS devices are formed in a single substrate with fully isolated wells and retrograde well doping. The retrograde well doping results from a process in which the complementary wells are formed in a silicon substrate and heavily doped collector regions formed at the surface. The wafer is then inverted and the backside of the wafer ground away exposing the retrograde doped wells. With appropriate well doping complementary IGBT devices can be integrated with bipolar and/or DMOS devices in the same substrate. Trench technology is used for isolation.
    Type: Grant
    Filed: August 27, 1999
    Date of Patent: October 31, 2000
    Assignee: Lucent Technologies Inc.
    Inventor: Muhammed Ayman Shibib
  • Patent number: 6137147
    Abstract: A bipolar transistor has a semiconductor region of a first conductivity type. A collector region of the first conductivity type and a base region of a second conductivity type are disposed within the semiconductor region. An emitter region of the first conductivity type and a base electrode region of the second conductivity type are disposed within a surface of the base region in self-alignment arrangement. At least one polycrystalline silicon layer is disposed on the entire surface of the base region except for portions of the surface of the base region overlying the emitter region and the base electrode region.
    Type: Grant
    Filed: February 19, 1999
    Date of Patent: October 24, 2000
    Assignee: Seiko Instruments Inc.
    Inventor: Naoto Saitou
  • Patent number: 6117718
    Abstract: A method for forming bipolar junction transistor with high gain via formulation of high voltage device in deep submicron process is disclosed. A substrate including a first part, a second part, and a third part is primarily provided; then, a first well in the first part and a second well in the second part are formed. A plurality of field oxide regions are formed on said substrate; subsequently, two third wells are formed in said third part. The following steps are to form a fourth well in said first well in said first part and two fifth wells in said second well in said second part; and to form a first gate on said first part between said two third wells, and a second gate on said second part between said two fifth wells. Next, a first spacer against said first gate and a second spacer against said second gate are formed. Further, first ions are introduced into said first part to serve as a collector region, and into said third part to serve as a first source/drain region.
    Type: Grant
    Filed: August 31, 1999
    Date of Patent: September 12, 2000
    Assignee: United Microelectronics Corp.
    Inventors: Ching-Chun Hwang, Sheng-Hsiung Yang
  • Patent number: 6093595
    Abstract: A method of forming a complementary metal-oxide-semiconductor (CMOS) integrated circuit, and the integrated circuit so formed, are disclosed. After the formation of a p-type well (4) and an n-type well (6) into which the transistors are to be formed; and gate structures (8n, 8p) overlying the surfaces of these wells (4, 6), a doped insulating layer (20) is formed overall, for example by way of chemical vapor deposition. The doped insulating layer (20) is, according to the preferred embodiment of the invention, silicon dioxide that is doped with boron. In the preferred embodiment of the invention, the portion of the doped insulating layer (20) overlying the p-type well (4) is removed, and ion implantation of n-type dopant is then performed. The remaining portion of the doped insulating layer (20) protects the n-type well (6) from the n-type ion implantation steps.
    Type: Grant
    Filed: September 29, 1998
    Date of Patent: July 25, 2000
    Assignee: Texas Instruments Incorporated
    Inventor: Hiroyuki Kurino
  • Patent number: 6090652
    Abstract: Disclosed is a manufacturing method of semiconductor device which can simplify the manufacturing procedures for transistors with different gate insulation film thickness in the same substrate. According to the present invention, a manufacturing method for semiconductor device having NMOS and PMOS transistors with gate insulation films of different thickness from each other, is formed by the following processes. First, a semiconductor substrate in which a low voltage NMOS transistor region, a high voltage NMOS transistor region, a low voltage PMOS transistor region, and a high voltage PMOS transistor region are defined by isolation films, is provided. Next, a N well is formed in the low and high voltage PMOS transistor regions and threshold voltage adjustment ions for high voltage PMOS transistor are then implanted into the N well.
    Type: Grant
    Filed: December 22, 1997
    Date of Patent: July 18, 2000
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventor: Jae-Kap Kim
  • Patent number: 6077736
    Abstract: A method of fabricating a semiconductor device includes the steps of preparing a semiconductor substrate having a first region and a second region, forming a first gate electrode and a second gate electrode over the semiconductor substrate at the first and second regions, respectively, implanting a first impurity ion into the substrate of the first region using the first gate electrode as a mask, implanting a second impurity ion into the substrate of the second region using the second gate electrode as a mask, forming sidewall spacers at both sides of each of the first and second gate electrodes, and implanting the second impurity ion into the first and second regions using the first and second gate electrodes and the sidewall spacers as masks.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: June 20, 2000
    Assignee: LG Semicon Co., Ltd.
    Inventors: Hyun Sang Hwang, Jae Gyung Ahn
  • Patent number: 6071767
    Abstract: An integrated circuit using high-performance bipolar and CMOS transistor elements on a single chip is fabricated by a simplified process requiring minimal, if any, changes in the process used for forming either type of device in accordance with a variety of possible device designs. The method according to the invention makes maximal use of self-aligned and self-masking processes to reduce the number of processing steps. The number of processing steps is further reduced by performing some steps concurrently on different device types. Further, the masking steps which are employed are reasonably misregistration tolerant, resulting in high manufacturing yield for the process. Consequently, the process according to the invention substantially eliminates the existence of trade-offs between element performance, integration density and process complexity and cost when plural technologies are integrated on the same chip.
    Type: Grant
    Filed: June 17, 1992
    Date of Patent: June 6, 2000
    Assignee: International Business Machines Corporation
    Inventors: Michael Monkowski, Seiki Ogura, Nivo Rovedo, Joseph Francis Shepard
  • Patent number: 6030864
    Abstract: A method of fabricating a bipolar transistor concurrently with an MOS device comprising the steps of forming an NPN bipolar transistor by providing a semiconductor wafer (1) having a semiconductor region (3) of predetermined conductivity type having a surface. An emitter region (33) and a collector contact region (35) are formed in and extend to the surface of the semiconductor region (3) of predetermined conductivity type with an implant of the predetermined conductivity type. An intrinsic base region (43) is formed extending to the surface by implanting an impurity of opposite conductivity type in the semiconductor region (3) isolating the emitter region (33) from the semiconductor region of predetermined conductivity type. An insulating layer (49) is formed on the semiconductor region of predetermined conductivity type extending over all transitions at the surface of the predetermined conductivity type to the opposite conductivity type.
    Type: Grant
    Filed: April 11, 1997
    Date of Patent: February 29, 2000
    Assignee: Texas Instruments Incorporated
    Inventors: Andrew T. Appel, Frank S. Johnson
  • Patent number: 5989963
    Abstract: A method of manufacturing a semiconductor device with a steep retrograde profile. The threshold voltage adjust dopant layer and the punchthrough prevent dopant layer are formed in the substrate. All surface capping layers are removed from the active device regions and, the semiconductor device is placed in a chamber and a high vacuum is established after which an inert atmosphere is introduced into the chamber. The anneal to repair the damage to the lattice and to activate the dopant ions in the dopant layers is done in the inert atmosphere with the surface of the substrate maintained clean, that is, free from a capping oxide or other layer formed on the surface of the substrate.
    Type: Grant
    Filed: July 21, 1997
    Date of Patent: November 23, 1999
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Scott D. Luning, David C. Greenlaw, Jonathan Fewkes
  • Patent number: 5972766
    Abstract: A method of manufacturing a transistor capable of obtaining a BICMOS while making the difference in the number of manufacturing processes from a CMOS smaller, includes the steps of: separating an element region in a semiconductor substrate; forming a emitter opening for deciding upon an emitter layer in an insulating film on the semiconductor substrate, forming a polysilicon film on the insulating film and in the emitter opening; implanting selectively impurity ions into the semiconductor substrate through the polysilicon film and the insulating film to form: a collector layer and a base layer; and performing heat treatment for activating impurities in the base layer and the collector layer and diffusing impurities into the semiconductor substrate from the polysilicon film to form an emitter diffused layer.
    Type: Grant
    Filed: February 28, 1997
    Date of Patent: October 26, 1999
    Assignee: NEC Corporation
    Inventor: Shuuji Kishi
  • Patent number: 5953603
    Abstract: Disclosed is a method for manufacturing a BiCMOS in which a complementary MOS transistor and a bipolar transistor are formed on the same substrate, comprising the steps of: providing a semiconductor substrate with impurities of a first conductivity type; forming field oxides for device isolation at the substrate to define a first group active region having two active regions and a second group active region having five active regions in series arrangement; forming a first mask pattern to expose three central active regions of the second group active region; forming a buried layer of a second conductivity type at a first depth from surfaces of the three central active regions using the first mask pattern; forming a second mask pattern to expose either one active region of the first group active region and two active regions at both edge portions of the second group active region; forming first well regions of the second conductivity type in which the impurities of the second conductivity type are distributed t
    Type: Grant
    Filed: June 24, 1998
    Date of Patent: September 14, 1999
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventor: Jae Kap Kim
  • Patent number: 5953600
    Abstract: The present invention relates to a method for fabricating an integrated circuit including complementary MOS transistors and a bipolar transistor of NPN type, including the steps of: forming MOS transistors in an epitaxial layer, coating the entire structure with a double protection layer, forming in an opening of this double layer the emitter-base of the bipolar transistor, a specific collector diffusion being formed in the epitaxial layer under the emitter-base region, and reopening the double protection layer at the locations where it is desired to perform silicidations.
    Type: Grant
    Filed: November 13, 1997
    Date of Patent: September 14, 1999
    Assignee: SGS-Thomson Microelectronics S.A
    Inventor: Yvon Gris
  • Patent number: 5907779
    Abstract: An integrated circuit is fabricated by forming first source and drain regions and contact regions which electrically contact respective first source and drain regions, for first field effect transistors in an integrated circuit. Then, second source and drain regions for second field effect transistors in the integrated circuit are formed. By simultaneously forming landing pads which electrically contact the integrated circuit substrate between first spaced apart gates, and doping the integrated circuit substrate which electrically contacts the landing pads, an additional protective layer may not be needed, thereby simplifying the fabrication process.
    Type: Grant
    Filed: October 15, 1996
    Date of Patent: May 25, 1999
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jin-gyoo Choi
  • Patent number: 5874329
    Abstract: The present invention comprises a method for controlling a threshold voltage through a semiconductor substrate of a first conductivity type (the type being an n- or p- type in a MOSFET) without the need for a blanket implant for either long or short channel devices. A gate structure having opposed lateral edges is formed adjacent a surface of the semiconductor substrate and over a channel region of the substrate. The substrate is rotated around a rotation axis normal to the surface of the substrate to a first rotation position. Ions of a first conductivity type are then implanted into the channel region, using the gate structure as a mask, at an oblique angle relative to the surface normal of the substrate. The substrate is then rotated to a second rotation position approximately 180 degrees from the first rotation position. Ions of the first conductivity type are then implanted into the channel region, using the gate structure as a mask, at the oblique angle relative to the surface of the substrate.
    Type: Grant
    Filed: December 5, 1996
    Date of Patent: February 23, 1999
    Assignee: LSI Logic Corporation
    Inventors: Paul Neary, Lindor E. Henrickson
  • Patent number: 5851864
    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: October 22, 1997
    Date of Patent: December 22, 1998
    Assignee: Harris Corporation
    Inventors: Akira Ito, Michael David Church
  • Patent number: 5851863
    Abstract: An n-type buried layer and an n-type epitaxial layer that becomes a collector layer of a pnp transistor are formed on a semiconductor substrate. A well and the collector layer are formed. Ions of an n-type impurity are implanted through a photoresist mask, to form an intrinsic base layer of the pnp transistor and a PT-VT diffusion layer with punchthrough stopper and threshold control functions of a pMOSFET. Ions of a p-type impurity are implanted through a photoresist mask at a shallow implantation depth than the previous step, to form an intrinsic base layer of an npn transistor and a channel dope layer of the pMOSFET. A buried channel is formed under the gate of the pMOSFET. Therefore pMOSFETs with good characteristics can be obtained. In this way, the present invention achieves bipolar transistors and MOSFETs with good characteristics, without having to increase the number of fabrication steps and the number of photoresist masks.
    Type: Grant
    Filed: April 8, 1996
    Date of Patent: December 22, 1998
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Taizo Fujii, Takehiro Hirai, Sugao Fujinaga
  • Patent number: 5763931
    Abstract: A semiconductor device having the SOI structure is provided, which enables to reduce the size of components compared with the conventional semiconductor devices. The device contains a first insulator film formed on a semiconductor substrate, and semiconductor islands formed on the first insulator film. Each of the islands has an electronic component. The device further contains semiconductor sidewalls formed to surround the respective islands. The sidewalls are contacted with outer sides of the corresponding islands. Electrodes are formed outside the islands to be contacted with the corresponding sidewalls. A second insulator film is formed on the exposed first insulator film from the islands to laterally isolate the respective islands and the corresponding sidewalls from each other. The electronic components are electrically connected to the respective electrodes through the corresponding sidewalls.
    Type: Grant
    Filed: September 21, 1995
    Date of Patent: June 9, 1998
    Assignee: NEC Corporation
    Inventor: Mitsuhiro Sugiyama
  • Patent number: 5637516
    Abstract: A method for producing complementary MOS and bipolar transistors on the same semiconductor wafer, includes producing buried zones of differing conductivity, producing n- and p-doped wells for corresponding transistors, and producing field oxide regions and insulated gate electrodes of the MOS transistors. After production of the field oxide regions, highly doped n-regions extending from a surface of the semiconductor wafer to a buried n-doped zone are produced with a first mask for producing a collector zone of an npn transistor and a base zone of a pnp transistor. After the production of the insulated gate electrodes, a first silicon layer is applied over the entire surface and doped with p-atoms. An auxiliary layer is applied on the first silicon layer over the entire surface. The auxiliary layer and the first silicon layer are structured with a second mask.
    Type: Grant
    Filed: July 12, 1995
    Date of Patent: June 10, 1997
    Assignee: Siemens Aktiengesellschaft
    Inventor: Karlheinz Muller
  • Patent number: 5618743
    Abstract: A process is disclosed (hereafter referred to as the "BiCDMOS Process") which simultaneously forms 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: June 5, 1995
    Date of Patent: April 8, 1997
    Assignee: Siliconix incorporated
    Inventors: Richard K. Williams, Hamza Yilmaz, Michael E. Cornell, Jun W. Chen
  • Patent number: RE36441
    Abstract: This invention discloses a semiconductor device comprising a semiconductor substrate, a first conducting layer formed on the surface of the semiconductor substrate, an insulating layer formed above the semiconductor substrate, the insulating layer having a contact hole reaching the first conducting layer to expose it, a second conducting layer formed on the insulating layer, the sidewall of the contact hole, and the first conducting layer, and an anti-oxidation layer formed on at least part of the surface of the second conducting layer.
    Type: Grant
    Filed: May 28, 1998
    Date of Patent: December 14, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yusuke Kohyama