Fet Configuration Adapted For Use As Static Memory Cell Patents (Class 257/903)
  • Publication number: 20010050442
    Abstract: A three-dimensional flash array structure and the fabrication method thereof. The three-dimensional flash memory array structure disclosed in the invention can be expanded volumetrically, so that a memory cell with large capacity can be manufactured in a unit area to increase the memory capacity.
    Type: Application
    Filed: March 21, 2001
    Publication date: December 13, 2001
    Inventor: Robin Lee
  • Patent number: 6329693
    Abstract: A semiconductor memory device has a silicon substrate 10. A first embedded layer 11 is formed in the silicon substrate 10 under a p-well 18 in an area below a region where a drain 36 of a driver transistor 30 is located. The first embedded layer 11 makes a junction with the p-well 18. Also, the first embedded layer 11 is formed below an n-well 16 and contacts the n-well 16. When the drain 36 of the driver transistor 30 is at a voltage of 3V, &agr;-ray may pass through the p-well 18, the first embedded layer 11 and the silicon substrate 10. As a result, electron-hole pairs are cut. Due to the presence of the p-n junction that is formed by the p-well 18 and the first embedded layer 11, only electrons in the p-well 18 are drawn to the drain 36. As a result, a fall in the drain voltage of 3V is reduced. As a consequence, the device structure makes it difficult to destroy retained data.
    Type: Grant
    Filed: June 9, 2000
    Date of Patent: December 11, 2001
    Assignee: Seiko Epson Corporation
    Inventor: Takashi Kumagai
  • Publication number: 20010046737
    Abstract: A semiconductor memory device and a fabricating method thereof are provided. In the course of forming a buried contact hole after forming a bit line pattern, the buried contact hole is formed by a self aligned contact process using capping layers included in the bit line pattern, thereby securing an overlap margin. Formation of a deep inner cylinder type capacitor unit prevents a bridge defect between lower electrodes of the capacitor and suppresses the occurrence of particles while simplifying the fabrication process. Furthermore, a mechanism for forming a second metal contact hole can simplifies the problems related to etching and filling of the second metal contact hole.
    Type: Application
    Filed: March 16, 2001
    Publication date: November 29, 2001
    Inventors: Tae-Hyuk Ahn, Sang-Sup Jeong
  • Patent number: 6323557
    Abstract: An improved method and structure which increases the alignment tolerances in multiple, singularized plugs are provided. The invention discloses a novel method for forming individual plug contacts with increased surface area for improved registration between semiconducting layers. Also the improved plug contacts are particularly well suited to receiving contact formations which have any taper to them. IGFETS and other devices formed from this design can be used in a variety of beneficial applications, e.g. logic or memory.
    Type: Grant
    Filed: February 23, 1999
    Date of Patent: November 27, 2001
    Assignee: Micron Technology, Inc.
    Inventor: Thomas A. Figura
  • Publication number: 20010042926
    Abstract: The drain of a drive transistor Q3 and the drain of a load transistor Q5 are connected by a first drain-drain contact layer. The drain of a drive transistor Q4 and the drain of a load transistor Q6 are connected by a second drain-drain contact layer. The gate electrodes of the drive transistor Q3 and the load transistor Q5 (a first gate electrode layer) are connected to the second drain-drain contact layer by a first drain-gate contact layer. The gate electrodes of the drive transistor Q4 and the load transistor Q6 (a second gate electrode layer) are connected to the first drain-drain contact layer by the second drain-gate contact layer.
    Type: Application
    Filed: December 15, 2000
    Publication date: November 22, 2001
    Inventors: Takashi Kumagai, Masahiro Takeuchi, Satoru Kodaira, Takafumi Noda
  • Patent number: 6316812
    Abstract: A memory cell power supply circuit includes: a memory cell power supply PMOS transistor connected between a power supply node and a power supply potential, a diode-connected transistor provided between a gate of the memory cell power supply transistor and the power supply potential, and a resistor provided between the gate of the memory cell power supply transistor and a ground potential. During a writing operation when a value of current flowing to the memory cell is high, if the power supply potential increases, a cell power supply potential down-converted by a greater amount is supplied to the memory cell.
    Type: Grant
    Filed: May 4, 2000
    Date of Patent: November 13, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Hideaki Nagaoka
  • Patent number: 6307217
    Abstract: A static random access memory comprising memory cells each composed of transfer MISFETs controlled by word lines and of a flip-flop circuit made of driver MISFETs and load MISFETs. The top of the load MISFETs is covered with supply voltage lines so that capacitor elements of a stacked structure are formed between the gate electrodes of the load MISFETs and the supply voltage lines.
    Type: Grant
    Filed: January 14, 1994
    Date of Patent: October 23, 2001
    Assignees: Hitachi, Ltd., Hitachi ULSI Engineering Corp.
    Inventors: Shuji Ikeda, Satoshi Meguro, Kyoichiro Asayama, Eri Fujita, Koichiro Ishibashi, Toshiro Aoto, Sadayuki Morita, Atsuyoshi Koike, Masayuki Kojima, Yasuo Kiguchi, Kazuyuki Suko, Fumiyuki Kanai, Naotaka Hashimoto, Toshiaki Yamanaka
  • Publication number: 20010030372
    Abstract: A semiconductor memory device comprising first and second gate-gate connecting layers, first and second drain-drain connecting layers, and first and second drain-gate connecting layers. The first and second gate-gate connecting layers respectively connect a gate of a driver transistor to a gate of a load transistor. The first and second drain-drain connecting layers are formed over a first interlayer dielectric and have a refractory metal nitride layer. The first and second drain-drain connecting layers respectively connect a drain of the driver transistor to a drain of the load transistor. The first and second drain-gate connecting layers are formed over a second interlayer dielectric, and respectively connect the first drain-drain connecting layer to the second gate-gate connecting layer, and the second drain-drain connecting layer to the first gate-gate connecting layer.
    Type: Application
    Filed: January 12, 2001
    Publication date: October 18, 2001
    Inventors: Katsumi Mori, Kei Kawahara, Yoshikazu Kasuya
  • Patent number: 6303966
    Abstract: An SRAM cell and method for fabricating the same including first and second access transistors, first and second drive transistors, and first and second load resistors. A first terminal of the first access transistor, a gate terminal of the second drive transistor, and a first load resistor terminal are connected to one another to form a first cell node terminal. A first terminal of the second access transistor, a gate terminal of the first drive transistor, and a second load resistor terminal are connected to one another to form a second cell node terminal. The SRAM cell includes a gate electrode of each of the first and second drive transistors arranged over a semiconductor substrate in a first direction, and a gate electrode of each of the first and second access transistors arranged in the first direction overlapped with portions of the gate electrodes of the first and second drive transistors.
    Type: Grant
    Filed: October 6, 1999
    Date of Patent: October 16, 2001
    Assignee: LG Semicon Co., Ltd.
    Inventor: Joon Young Park
  • Patent number: 6303965
    Abstract: The invention encompasses resistors comprising a thin layer of dielectric material and methods of forming such resistors. The invention also encompasses integrated circuitry comprising such resistors, including SRAM circuitry, and encompasses methods of forming such integrated circuitry. In one aspect, the invention includes a resistor construction for electrically connecting a first node location to a second node location comprising: a) a first conductive layer in electrical connection with the first node location; b) a second conductive layer in electrical connection with the second node location; and c) a dielectric material intermediate the first conductive layer and the second conductive layer and having a thickness of from about 15 Angstroms to about 60 Angstroms.
    Type: Grant
    Filed: August 20, 1999
    Date of Patent: October 16, 2001
    Assignee: Micron Technology, Inc.
    Inventor: Klaus Florian Schuegraf
  • Publication number: 20010028059
    Abstract: The present invention describes the use of two semiconductor layers, a thin film (TF) layer and a bulk Si wafer layer, to make high density and high speed merged logic and memory IC chips. The memory cells use three-dimensional (3D) SRAM structures. Two kinds of 3D logic cells are disclosed. 3D form of the differential cascode voltage switch (DCVS) architecture, and a 3D form of the DCVS with pass gate (DCVSPG) logic architecture. A high density “system on chip” architecture is described. The high density is achieved by locating large PMOS transistors in the TF Si layer, and the fast NMOS transistors in a bulk Si wafer layer. A single process sequence to simultaneously make the logic and memory circuits on the IC chip is also described.
    Type: Application
    Filed: May 18, 2001
    Publication date: October 11, 2001
    Inventors: Philip George Emma, Wei Hwang, Stephen McConnell Gates
  • Publication number: 20010028099
    Abstract: A patterned polysilicon film is formed over a silicon substrate with an interlayer insulating film therebetween. Then heavily doped regions as well as a lightly doped region are formed on the polysilicon film. The entire polysilicon film is covered with an SiO2 film. The polysilicon film is hydrogenated, while an SiNx film is formed over the entire SiO2 film, by LPCVD using a gas comprising nitrogen and hydrogen.
    Type: Application
    Filed: March 30, 2001
    Publication date: October 11, 2001
    Applicant: NEC CORPORATION
    Inventor: Nolifumi Sato
  • Patent number: 6297531
    Abstract: A vertical Field Effect Transistor (FET) that may be an N-type FET (NFET) or a P-type FET (PFET); a multi-device vertical structure that may be two or more NFETs or two or more PFETS; logic gates including at least one vertical FET or at least one multi-device vertical; a Static Random Access Memory (SRAM) cell and array including at least one vertical FET; a memory array including at least one such SRAM cell; and the process of forming the vertical FET structure, the vertical multi-device (multi-FET) structure, the logic gates and the SRAM cell. The vertical FETs are epitaxially grown layered stacks of NPN or PNP with the side of a polysilicon gate layer adjacent the device's channel layer. The multi-FET structure may be formed by forming sides of two or more gates adjacent to the same channel layer or, by forming multiple channel layers in the same stack, e.g., PNPNP or NPNPN, each with its own gate, i.e., the side of a polysilicon gate layer.
    Type: Grant
    Filed: January 5, 1998
    Date of Patent: October 2, 2001
    Assignee: International Business Machines Corporation
    Inventors: Michael D. Armacost, Claude L. Bertin, Erik L. Hedberg, Jack A. Mandelman
  • Patent number: 6291883
    Abstract: The present invention provides a static random-access memory (SRAM) device that comprises a substrate having an insulator and a gate formed thereover, where the insulator electrically insulates the gate from the substrate, and a local conductive layer that is formed on the gate structure and that extends from the gate and onto the substrate. The local conductive layer is connectable to a conductive interconnect structure to connect the gate electrically to an other portion of the SRAM device. The SRAM device, in one embodiment, is part of a complementary metal oxide semiconductor (CMOS). However, it will be appreciated by those who are of ordinary skill the art that the present invention may be used in various types of metal oxide semiconductors and similar semiconductor devices in general.
    Type: Grant
    Filed: March 3, 1999
    Date of Patent: September 18, 2001
    Assignee: Agere Systems Guardian Corp.
    Inventors: William J. Nagy, Kuo-Hua Lee
  • Patent number: 6285088
    Abstract: An integrated circuit having a memory cell array in which the strapping of cell components is accomplished within a memory cell. In one embodiment the strapping 750, 752, 756 is placed between the moats 706,724 of transistors that compose cross-coupled inverters within a static random access memory cell.
    Type: Grant
    Filed: May 6, 1999
    Date of Patent: September 4, 2001
    Assignee: Texas Instruments Incorporated
    Inventor: Sudhir K. Madan
  • Publication number: 20010017387
    Abstract: A method is provided for forming buried source line in semiconductor devices. It is known in the art to form buried contacts on the surface of a semiconductor substrate. The present invention discloses a method of fabricating a semiconductor device, particularly a memory cell, having both the source region and the source line buried within the substrate. The source line is formed in a trench in the substrate over the source region. The trench walls are augmented with voltage anti-punch-through protection. The trench also provides the attendant advantages of extended sidewall area, smaller sheet resistance, and yet smaller cell area, therefore, smaller chip size, and faster access time as claimed in the embodiments of this invention. The buried source disclosed here is integrated with source line which is also buried within the substrate.
    Type: Application
    Filed: February 20, 2001
    Publication date: August 30, 2001
    Applicant: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY
    Inventors: Chia-Ta Hsieh, Jenn Tsao, Di-Son Kuo, Yai-Fen Lin, Hung-cheng Sung
  • Publication number: 20010017807
    Abstract: A semiconductor memory device includes bit lines which transfer data of memory cells, a plurality of first sense amplifier circuits connected to odd-number lines of the bit lines, a plurality of second sense amplifier circuits connected to even-number lines of the bit lines, and a clamp-voltage generation circuit which supplies a first clamp voltage to the first sense amplifier circuits, and supplies a second clamp voltage to the second sense amplifier circuits, whereby during test operation, the odd-number lines are clamped to the first clamp voltage, and the even-number lines are clamped to the second clamp voltage.
    Type: Application
    Filed: February 23, 2001
    Publication date: August 30, 2001
    Applicant: Fujitsu Limited
    Inventor: Shinya Fujioka
  • Patent number: 6279144
    Abstract: A hardware design technique allows checking of design system language (DSL) specification of an element and schematics of large macros with embedded arrays and registers. The hardware organization reduces CPU time for logical verification by exponential order of magnitude without blowing up a verification process or logic simulation. The hardware organization consists of horizontal word level rather than bit level. A memory array cell comprises a pair of cross-coupled inverters forming a first latch for storing data. The first latch has an output connected to a read bit line. True and complement write word and bit line input to the first latch. A first set of pass gates connects between the true and complement write word and bit line inputs via gates and the input of said first latch. The first set of pass gates is responsive to a first clock via a second pass gate. A pair of cross-coupled inverters forms a second latch of a Level Sensitive Scan Design (LSSD).
    Type: Grant
    Filed: August 19, 1999
    Date of Patent: August 21, 2001
    Assignee: International Business Machines Corporation
    Inventors: Walter Harvey Henkels, Wei Hwang, Rajiv Vasant Joshi, Albert Thomas Williams
  • Publication number: 20010011735
    Abstract: The semiconductor memory device of the present invention comprises: memory cells arranged in a matrix; word lines extending in a row direction; bit line pairs extending in a column direction; exchange blocks for exchanging the bit lines of the different neighboring bit line pairs.
    Type: Application
    Filed: January 31, 2001
    Publication date: August 9, 2001
    Applicant: NEC CORPORATION
    Inventor: Koichi Takeda
  • Patent number: 6271542
    Abstract: The present invention describes the use of two semiconductor layers, a thin film (TF) layer and a bulk Si wafer layer, to make high density and high speed merged logic and memory IC chips. The memory cells use three-dimensional (3D) SRAM structures. Two kinds of 3D logic cells are disclosed. 3D form of the differential cascode voltage switch (DCVS) architecture, and a 3D form of the DCVS with pass gate (DCVSPG) logic architecture. A high density “system on chip” architecture is described. The high density is achieved by locating large PMOS transistors in the TF Si layer, and the fast NMOS transistors in a bulk Si wafer layer. A single process sequence to simultaneously make the logic and memory circuits on the IC chip is also described.
    Type: Grant
    Filed: December 8, 1997
    Date of Patent: August 7, 2001
    Assignee: International Business Machines Corporation
    Inventors: Philip George Emma, Wei Hwang, Stephen McConnell Gates
  • Patent number: 6271063
    Abstract: A six transistor static random access memory (SRAM) cell with thin-film pull-up transistors and method of making the same includes providing two bulk silicon pull-down transistors of a first conductivity type, two active gated pull-up thin-film transistors (TFTs) of a second conductivity type, two pass gates, a common word line, and two bit line contacts. The bulk silicon pull-down transistors, two active gated pull-up TFTs, and two pass gates are connected at four shared contacts. In addition, the two bulk silicon pull-down transistors and the two active gated pull-up TFTs are formed with two polysilicon layers, a first of the polysilicon layers (poly1) is salicided and includes poly1 gate electrodes for the two bulk silicon pull-down transistors. A second of the polysilicon layers (poly2) includes desired poly2 stringers disposed along side edges of the poly1 gate electrodes, the desired poly2 stringers forming respective channel regions of the pull-up TFTs.
    Type: Grant
    Filed: June 14, 2000
    Date of Patent: August 7, 2001
    Assignee: STMicroelectronics, Inc.
    Inventors: Tsiu Chiu Chan, Frank Randolph Bryant
  • Patent number: 6271569
    Abstract: According to a semiconductor device and a method of manufacturing the same, a storage node has an increased capacity, and a resistance against soft error is improved. A GND interconnection is formed on a first interconnection layer including storage node portions with a dielectric film therebetween. Thereby, the storage node portions, the dielectric film, and the GND interconnection form a capacity element of the storage node portion. The first interconnection layer is arranged symmetrically around the center of the memory cell, and a plurality of memory cells having the same layout and neighboring to each other are arranged along the word lines.
    Type: Grant
    Filed: January 16, 1998
    Date of Patent: August 7, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoshiyuki Ishigaki, Hiroki Honda
  • Patent number: 6252294
    Abstract: A semiconductor device and a semiconductor storage device having an SOI structure and being enable sufficient gettering performance without imposing limitations on the freedom of design of an LSI circuit. A semiconductor device includes a semiconductor wafer of SOI structure which has a insulation layer and a silicon layer provided thereon, wherein the semiconductor wafer includes a plurality of element fabrication regions where semiconductor elements are fabricated, and a cutting region provided between the element fabrication regions. Gettering sites are formed in the cutting region by means of embedding a gettering member into grooves of predetermined depth.
    Type: Grant
    Filed: November 12, 1999
    Date of Patent: June 26, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Nobuyoshi Hattori, Hideki Naruoka, Hidekazu Yamamoto
  • Patent number: 6243286
    Abstract: An SRAM comprises first, second and third conductive layers. The first conductive layer is a gate electrode for a first load transistor and a first driver transistor. The second conductive layer branches from the first conductive layer on a field oxide region and is electrically connected to a second driver transistor active region. The third conductive layer is a gate electrode for a second load transistor and a second driver transistor. The third conductive layer is electrically connected to a first load transistor active region. The width of part of the second conductive layer on the field oxide region is less than the width of the first conductive layer.
    Type: Grant
    Filed: July 26, 1999
    Date of Patent: June 5, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Takashi Kumagai, Junichi Karasawa, Kazuo Tanaka, Kunio Watanabe
  • Publication number: 20010002056
    Abstract: An SRAM cell is described which has a reduced cell area, and a reduced processing cost from conventional SRAM's. A fabrication process is described where self-aligned contacts to substrate active area and contact to a first layer of polysilicon are formed in one etch step. Electrical connection between the substrate and polysilicon is provided through a conductive layer coupled to the contacts. Self aligned contacts are fabricated to contact the active area.
    Type: Application
    Filed: January 10, 2001
    Publication date: May 31, 2001
    Applicant: Micron Technology, Inc.
    Inventor: H. Montgomery Manning
  • Patent number: 6240009
    Abstract: A single-ended read, differential write CMOS SRAM cell has two inverters connected in a regenerative feedback circuit. Each inverter includes two complementary FETs. FETs of the same type in each inverter have differing gate widths and/or drive currents. The cell includes pass gate FETs having gate regions of approximately the same widths but differing lengths.
    Type: Grant
    Filed: February 2, 2000
    Date of Patent: May 29, 2001
    Assignee: Hewlett-Packard Company
    Inventors: Samuel D. Naffziger, Donald R. Weiss
  • Patent number: 6239458
    Abstract: This is a method of forming an SRAM transistor cell on a well in a doped semiconductor substrate. Form a gate oxide layer and a split gate layer with buried contact regions in the well and openings through the split gate layer and the gate oxide layer to the well. Form an intermediate conductor layer and a hard silicon oxide mask layer and define gate conductors. Form lightly doped source/drain regions, form spacers and source/drain regions in the well. Form a first inter-conductor dielectric layer on the cell. Define a self-aligned contact region in the cell above source/drain regions. Form a second conductor layer over the cell and patterning the second conductor layer to form a via in the self-aligned contact region. Form a second inter-conductor dielectric layer on the cell, a third conductor layer over the cell and patterning the third conductor layer to form a first resistor connected to the self-aligned contact region.
    Type: Grant
    Filed: November 18, 1998
    Date of Patent: May 29, 2001
    Assignee: Taiwan Semiconductor Manufacturing Company
    Inventors: Jhon-Jhy Liaw, Jin-Yuan Lee
  • Patent number: 6236117
    Abstract: A semiconductor device including a shunt interconnection which operates at higher speed and permits high density integration is provided. In the semiconductor device including the shunt interconnection, a shunt connection region for a word line and a first shunt interconnection including a metal are formed in the memory cell region. In the memory cell region, shunt connection region and shunt interconnection are electrically connected with each other through a word line contact plug formed in a contact hole.
    Type: Grant
    Filed: March 26, 1998
    Date of Patent: May 22, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoshiyuki Ishigaki, Hiroki Honda
  • Patent number: 6232670
    Abstract: First and second memory cells of an SRAM comprises first, second, and third conductive layers. The first conductive layer is a gate electrode for a first load transistor and a first driver transistor. The second conductive layer diverges from the first conductive layer on a field oxide region and is electrically connected to a second driver transistor active region. The third conductive layer is a gate electrode for a second load transistor and a second driver transistor. The third conductive layer is electrically connected to a first load transistor active region. The pattern of the first, second, and third conductive layers of the second memory cell is a rotated pattern of the first, second, and third conductive layers in the first memory cell at an angle of 180 degrees around an axis perpendicular to the main surface of a semiconductor substrate.
    Type: Grant
    Filed: July 26, 1999
    Date of Patent: May 15, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Takashi Kumagai, Junichi Karasawa, Kazuo Tanaka, Kunio Watanabe
  • Patent number: 6229212
    Abstract: An electrical interconnection method includes: a) providing two conductive layers separated by an insulating material on a semiconductor wafer; b) etching the conductive layers and insulating material to define and outwardly expose a sidewall of each conductive layer; c) depositing an electrically conductive material over the etched conductive layers and their respective sidewalls; and d) anisotropically etching the conductive material to define an electrically conductive sidewall link electrically interconnecting the two conductive layers. Such is utilizable to make thin film transistors and other circuitry.
    Type: Grant
    Filed: October 12, 1999
    Date of Patent: May 8, 2001
    Assignee: Micron Technology, Inc.
    Inventors: Charles H. Dennison, Monte Manning
  • Publication number: 20010000760
    Abstract: A method for forming an electrical interconnect overlying a buried contact region of a substrate is characterized by a deposition of a first polycrystalline silicon layer and the patterning and etching of same to form a via. The via is formed in the first polycrystalline silicon layer to expose the substrate and a second polycrystalline silicon layer is formed in the via to contact the substrate. Portions of the second polycrystalline silicon layer overlying the first polycrystalline silicon layer are removed eliminating any horizontal interface between the two polycrystalline silicon layers. The first polycrystalline silicon layer remaining after the etch is then patterned to form an electrical interconnect.
    Type: Application
    Filed: December 21, 2000
    Publication date: May 3, 2001
    Applicant: Micron Technology, Inc.
    Inventors: Martin C. Roberts, Sanh D. Tang
  • Patent number: 6222758
    Abstract: In the semiconductor memory device, the size in the row direction of the memory cell region having no through-hole therein is made smaller than that of the memory cell region having a through-hole therein. Thus, even if the semiconductor memory device has a double-layered bit line configuration and the size in the row direction of the memory cell region increases due to the through-hole connecting the bit lines in the first and second layers or the like, it is possible to prevent the increase in size of the memory cell region, and hence, the increase in area of the memory cell array.
    Type: Grant
    Filed: May 15, 2000
    Date of Patent: April 24, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Yoshiko Higashide
  • Patent number: 6204518
    Abstract: An SRAM cell comprising, at least, two driving transistors and two transfer transistors, and two load transistors each comprised of a TFT and disposed on these transistors through a layer insulation film, the load transistors having an active region comprising an Si film having improved crystallizability of amorphous Si by the solid phase growth technique using a catalytic element, and a barrier layer for preventing the catalytic element from diffusion into the driving transistors and the transfer transistors which is disposed between the layer insulation film and the load transistors.
    Type: Grant
    Filed: January 19, 2000
    Date of Patent: March 20, 2001
    Assignees: Sharp Kabushiki Kaisha, Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Albert O. Adan, Jun Koyama, Shunpei Yamazaki
  • Patent number: 6204538
    Abstract: The present invention discloses a static random access memory cell having a reduced cell size and method of manufacturing the same. According to the invention, the SRAM cell includes: a word line and a bit line; an access device connected to the word and bit lines, wherein in case that the word line is selected, the access device outputs data inputted from the bit line; a pull-up device connected to the access device as well as to a predetermined power voltage, wherein the pull-up device operates in pull-up manner according to the data inputted from the access device; and a pull-down device connected to the access device and the pull-up device as well as to a ground, wherein the pull-down device operates in pull-down manner according to the data inputted from the access devices.
    Type: Grant
    Filed: January 15, 1999
    Date of Patent: March 20, 2001
    Assignee: Hyundai Electronics Industries Co. Ltd.
    Inventor: Jae-Kap Kim
  • Patent number: 6198173
    Abstract: A method of forming an SRAM transistor cell on a doped semiconductor substrate with a halo region in transistors thereof by the steps including well formation, field isolation formation, threshold voltage implant, gate oxidation; deposition of polysilicon and patterning thereof into gate electrode; post etching anneal; N type LDD photolithography and ion implanting NMOS transistor devices; ion implant halo regions in a transistor; P type LDD photolithography and ion implanting PMOS transistor devices; spacer formation; N+ source/drain photolithography and ion implanting; and P+ source/drain photolithography and ion implanting.
    Type: Grant
    Filed: November 20, 1998
    Date of Patent: March 6, 2001
    Assignee: Taiwan Semiconductor Manufacturing Company
    Inventor: Jenn Ming Huang
  • Patent number: 6194765
    Abstract: An integrated electrical circuit has at least one memory cell, in which the memory cell is disposed in the region of a surface of a semiconductor substrate. The memory cell contains at least two inverters that are electrically connected to one another. The inverters each contain two complementary MOS transistors having a source, a drain and a channel, the channels of the complementary MOS transistors having different conductivity types. According to the invention, the integrated electrical circuit is constructed in such a way that the inverters are disposed perpendicularly to the surface of the semiconductor substrate. The source, the drain and the channel of the complementary MOS transistors are formed by layers which lie one on top of the other and are disposed in such a way that the complementary MOS transistors are situated one above the other. The invention furthermore relates to a method for fabricating the integrated electrical circuit.
    Type: Grant
    Filed: May 17, 1999
    Date of Patent: February 27, 2001
    Assignee: Siemens Aktiengesellschaft
    Inventors: Hans Reisinger, Reinhard Stengl, Ulrike Grüning, Volker Lehmann, Hermann Wendt, Josef Willer, Martin Franosch, Herbert Schäfer
  • Patent number: 6184539
    Abstract: A static memory cell having no more than three transistors. A static memory cell comprises a semiconductor substrate of a first conductivity type; a buried layer in the substrate, the buried layer having a second conductivity type opposite to the first conductivity type; a transistor formed over the buried layer, the transistor having a source of the second conductivity type, a gate, and a drain of the second conductivity type, the source having a depth in the substrate greater than the depth of the drain; and alternating layers of insulative and conductive material formed proximate the source, including two conductive layers and two insulative layers, one of the insulative layers being in junction relation to the source.
    Type: Grant
    Filed: May 4, 1998
    Date of Patent: February 6, 2001
    Assignee: Micron Technology, Inc.
    Inventors: Jeff Zhiqiang Wu, Joseph Karniewicz
  • Patent number: 6184588
    Abstract: An SRAM cell having a word line shorter than a bit line is provided. First and second driver transistors having first and second gate electrodes parallel to each other are formed on a semiconductor substrate, and a third gate electrode shared by first and second transfer transistors is formed between the first and the second gate electrodes. A word line electrically connected to the third electrode is perpendicular to the first and the second gate electrodes, and a pair of bit lines electrically connected to drain areas of the first and the second transfer transistors are perpendicular to the word line. Also, a pair of ground lines are electrically connected to the source areas of the first and the second driver transistors, and are parallel to the bit lines.
    Type: Grant
    Filed: April 26, 1999
    Date of Patent: February 6, 2001
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Han-soo Kim, Kyeong-tae Kim
  • Patent number: 6180998
    Abstract: A dynamic random access memory (DRAM) segment incorporates at least one shielding conductor spaced from a matrix of memory cells above the substrate and a well formed in the substrate which contains the memory cells. The shielding conductor primarily shields the memory cells from external noise signals created by other conductors. The isolating well primarily shields the memory cells from noise signals created by substrate currents and alpha particles. Among other features the DRAM employs a logically complementary pair of charge storage capacitors and differential sensing to avoid the influence of noise on a single memory capacitor. The shielding conductor is formed by a mesh of conductors or an integral conductor which overlays the matrix of cells and connects to the well. External power supplies and references are also connected to the well and the shielding conductors.
    Type: Grant
    Filed: March 30, 1998
    Date of Patent: January 30, 2001
    Assignee: LSI Logic Corporation
    Inventor: Harold S. Crafts
  • Patent number: 6178110
    Abstract: In a static memory cell including first and second drive MOS transistors, first and second MOS transfer transistors and first and second load elements, the drain of the first drive MOS transistor and the source of the first transfer MOS transistor are formed by a first impurity region in a semiconductor substrate, and the drain of the second drive MOS transistor and the source of the second transfer MOS transistor are formed by a second impurity region in the semiconductor substrate. Also, a first metal silicide layer is formed on the first impurity region and the gate of the second drive MOS transistor, and a second metal silicide layer is formed on the second impurity region and the gate of the the drive MOS transistor. Further, the first and second load elements are formed on the first and second metal silicide layers, respectively.
    Type: Grant
    Filed: February 27, 1998
    Date of Patent: January 23, 2001
    Assignee: NEC Corporation
    Inventor: Fumihiko Hayashi
  • Patent number: 6175138
    Abstract: In a memory device of an SRAM, a threshold voltage (Vthn) of each driving MOS transistor consisting of the N-type MOS transistor is set larger than a threshold voltage (Vthp) of each MOS transistor for selecting an address consisting of the P-type MOS transistor.
    Type: Grant
    Filed: April 19, 1999
    Date of Patent: January 16, 2001
    Assignee: NEC Corporation
    Inventor: Kenji Noda
  • Patent number: 6166447
    Abstract: A memory device of the present invention provides a stable operation and low voltage characteristics. An access device receives first and second data signals on first and second data lines, respectively, and is coupled to first and second nodes. A drive device is coupled to the access device at the first and second nodes. A voltage shifting device is coupled to at least one of the first and second nodes to change a voltage of at least one of the first and second nodes. The access device includes a first access transistor coupled to the first data line and the first node. The access device also includes a second access transistor coupled to the second data line and the second node. The first and second access transistors are responsive to a control signal.
    Type: Grant
    Filed: September 17, 1997
    Date of Patent: December 26, 2000
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventor: Sung Kye Park
  • Patent number: 6163054
    Abstract: The present invention introduces an SRAM cell which enhances immunity to soft errors and a manufacturing method thereof. A method of manufacturing an SRAM cell having access devices, pull-up devices and pull-down devices and forming a cell node junction in common junction regions of the pull-down devices and the access devices, the manufacturing method including the steps of: providing a semiconductor substrate of which active regions are difined and gate insulating layers and gates are formed on thereof; forming N.sup.- junction regions in the substrates of both sides of the gates for the pull-down devices region and the access devices region, wherein the N.sup.- junction regions formed in the cell node are separated therein and are adjacent to the gates thereof; forming the insulating layer spacers on both side-walls of the gates; and forming N.sup.+ junction regions in the substrate of both side of the spacers for the pull-down devices region and the access devices region.
    Type: Grant
    Filed: May 25, 1999
    Date of Patent: December 19, 2000
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventor: Jae-Kap Kim
  • Patent number: 6160298
    Abstract: According to a novel pattern layout of a full CMOS SRAM cell comprising first and second transfer, driver, and load transistors, six in total, the driver and load transistors are parallel to a buried word line. The first transfer transistor and the first driver transistor are alongside and parallel to one complementary data line and the second transfer transistor and the second driver transistor are alongside and parallel to the other complementary data line. Moreover, a power bus and a reference bus are parallel to and on both sides of each of the complementary data lines. Preferably, four gate electrodes of the first and second driver and load transistors are individually formed while the word line is used gate electrodes of the first and second transfer transistors.
    Type: Grant
    Filed: July 11, 1997
    Date of Patent: December 12, 2000
    Assignee: NEC Corporation
    Inventor: Hiroaki Ohkubo
  • Patent number: 6160294
    Abstract: A semiconductor device of the present invention includes an insulating layer covering a plurality of semiconductor elements formed in a semiconductor layer, an opening portion formed in the insulating layer respective conductive portions of the plurality of semiconductor elements in the insulating layer, and a conductive pattern formed in the opening portion for connecting respective conductive portions of the plurality of semiconductor elements.
    Type: Grant
    Filed: August 4, 1997
    Date of Patent: December 12, 2000
    Assignee: Fujitsu Limited
    Inventor: Koichi Hashimoto
  • Patent number: 6157564
    Abstract: An SRAM is provided in which adjacent contact holes cannot be connected and which can be miniaturized. An SRAM memory cell includes a gate electrode formed on a silicon substrate, and an interlayer insulation film covering the gate electrode. The interlayer insulation film has a contact hole which reaches an active region and a contact hole which reaches the gate electrode. The contact holes are positioned almost in a lattice manner.
    Type: Grant
    Filed: March 6, 2000
    Date of Patent: December 5, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kazuhito Tsutsumi
  • Patent number: 6147385
    Abstract: A full CMOS SRAM cell having the capability of having a reduced aspect ratio is described. The SRAM cell includes first and second transfer transistors of n-channel types, first and second driving transistors of the n-channel types and first and second load transistors of p-channel types. Each of the transistors has source and drain regions on opposite sides of a channel region formed in a semiconductor substrate and a gate over the channel region. The cell includes a first common region defined by the drain regions of the first transfer transistor and the first driving transistor connected in series therethrough. A second common region is defined by the drain regions of the second transfer transistor and the second driving transistor connected in series therethrough. The drain region of the first load transistor is disposed adjacent to the first common region between the first and second common regions.
    Type: Grant
    Filed: December 22, 1998
    Date of Patent: November 14, 2000
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Sung-Bong Kim, Ki-Joon Kim, Jong-Mil Youn
  • Patent number: 6146936
    Abstract: The present invention pertains to methods of forming integrated circuitry, methods of forming SRAM cells, and methods of reducing alpha particle inflicted damage to SRAM cells. Additionally, the present invention pertains to integrated circuitry. In one aspect, the invention includes a method comprising: a) forming at least one second conductivity type diffusion region beneath at least one of an SRAM cell pull-down device drain of a first conductivity type and an SRAM cell access device source of the first conductivity type; and b) not forming a second conductivity type diffusion region beneath at least one of a source of the SRAM cell pull-down device and a drain of the SRAM cell access device.
    Type: Grant
    Filed: December 11, 1998
    Date of Patent: November 14, 2000
    Assignee: Micron Technology, Inc.
    Inventor: H. Montgomery Manning
  • Patent number: 6140685
    Abstract: A static memory cell having no more than three transistors. A static memory cell is formed by providing a semiconductor substrate; forming a buried n-type layer in the substrate, the n-type layer having a first average n-type dopant concentration of at least 1.times.10.sup.16 ions/cm.sup.3 ; forming an n-channel transistor relative to the substrate over the buried n-type layer, the n-channel transistor having a source, a gate, and a drain, the source having a second average n-type dopant concentration of at least 1.times.10.sup.19 ions/cm.sup.3 and the drain having a third average n-type dopant concentration of at least 1.times.10.sup.19 ions/cm.sup.3, and the source having a depth deeper than the drain so as to be closer to the buried n-type layer than the drain; and forming a p-type region in junction with the source to define a tunnel diode between the p-type region and the source.
    Type: Grant
    Filed: April 30, 1999
    Date of Patent: October 31, 2000
    Assignee: Micron Technology, Inc.
    Inventors: Jeff Zhiqiang Wu, Joseph Karniewicz
  • Patent number: 6140684
    Abstract: A six transistor static random access memory (SRAM) cell with thin-film pull-up transistors and method of making the same includes providing two bulk silicon pull-down transistors of a first conductivity type, two active gated pull-up thin-film transistors (TFTs) of a second conductivity type, two pass gates, a common word line, and two bit line contacts. The bulk silicon pull-down transistors, two active gated pull-up TFTs, and two pass gates are connected at four shared contacts. In addition, the two bulk silicon pull-down transistors and the two active gated pull-up TFTs are formed with two polysilicon layers, a first of the polysilicon layers (poly1) is salicided and includes poly1 gate electrodes for the two bulk silicon pull-down transistors. A second of the polysilicon layers (poly2) includes desired poly2 stringers disposed along side edges of the poly1 gate electrodes, the desired poly2 stringers forming respective channel regions of the pull-up TFTs.
    Type: Grant
    Filed: June 24, 1997
    Date of Patent: October 31, 2000
    Assignee: STMicroelectronic, Inc.
    Inventors: Tsiu Chiu Chan, Frank Randolph Bryant