With Resistive Gate Electrode Patents (Class 257/364)
-
Publication number: 20090090971Abstract: A semiconductor device is disclosed. The device comprises a first MOSFET transistor. The transistor comprises a substrate, a first high-k dielectric layer upon the substrate, a first dielectric capping layer upon the first high-k dielectric, and a first gate electrode made of a semiconductor material of a first doping level and a first conductivity type upon the first dielectric capping layer. The first dielectric capping layer comprises Scandium.Type: ApplicationFiled: September 18, 2008Publication date: April 9, 2009Applicants: Interuniversitair Microelektronica Centrum vzw (IMEC), TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.Inventors: Shih-Hsun Chang, Lars-Ake Ragnarsson
-
Patent number: 7498621Abstract: A two-dimensional, temporally modulated electromagnetic wavefield, preferably in the ultraviolet, visible or infrared spectral range, can be locally detected and demodulated with one or more sensing elements. Each sensing element consists of a resistive, transparent electrode (E) on top of an insulated layer (O) that is produced over a semiconducting substrate whose surface is electrically kept in depletion. The electrode (E) is connected with two or more contacts (C1; C2) to a number of clock voltages that are operated synchronously with the frequency of the modulated wavefield. In the electrode and in the semiconducting substrate lateral electric fields are created that separate and transport photogenerated charge pairs in the semiconductor to respective diffusions (D1; D2) close to the contacts (C1; C2).Type: GrantFiled: June 5, 2003Date of Patent: March 3, 2009Assignee: MESA Imaging AGInventor: Peter Seitz
-
Publication number: 20080258225Abstract: MOS transistors having high-k spacers and methods for fabricating such transistors are provided. One exemplary method comprises forming a gate stack overlying a semiconductor substrate and forming an offset spacer about sidewalls of the gate stack. The offset spacer is formed of a high-k dielectric material that results in a low interface trap density between the offset spacer and the semiconductor substrate. First ions of a conductivity-determining impurity type are implanted into the semiconductor substrate using the gate stack and the offset spacer as an implantation mask to form spaced-apart impurity-doped extensions.Type: ApplicationFiled: April 20, 2007Publication date: October 23, 2008Applicant: ADVANCED MICRO DEVICES, INC.Inventors: Frank (Bin) YANG, Michael HARGROVE
-
Patent number: 7425736Abstract: A silicon layer with high resistance is provided. The silicon layer with high resistance is positioned on a substrate. Also, the silicon layer with high resistance includes a plurality of silicon material layers, and an interface layer between every two of the silicon material layers, wherein, the silicon material layers and the interface layer have dopants therein. The amount of implanted dopants is about 1*1014˜5*1015 ions/cm2, and the silicon material layers have different grain boundaries.Type: GrantFiled: June 7, 2005Date of Patent: September 16, 2008Assignee: United Microelectronics Corp.Inventor: Yu-Chi Yang
-
Patent number: 7391084Abstract: An LDMOS transistor device in an integrated circuit comprises a semiconductor substrate (10), a gate region (1) including a gate semiconductor layer region (2; 2?; 151) on top of a gate insulation layer region (3; 141), source (4) and drain (5, 7) regions, and a channel (6; 12) arranged beneath the LDMOS gate region, the channel interconnecting the LDMOS source and drain regions and having a laterally graded doping concentration. In order to obtain a lower parasitic capacitance coupling from the gate semiconductor region, the gate semiconductor layer region is provided with a laterally graded net doping concentration (P+N+; N+N?). A method for fabrication of the inventive LDMOS transistor device is further disclosed.Type: GrantFiled: June 17, 2004Date of Patent: June 24, 2008Assignee: Infineon Technologies AGInventors: Torkel Arnborg, Ulf Smith
-
Publication number: 20080023769Abstract: A semiconductor device includes an active region. A gate electrode is disposed on the active region. An isolation region adjoins the active region, and is recessed with respect to a top surface of the active region underlying the gate electrode. The isolation region may be recessed a depth substantially equal to a height of the gate electrode. In some embodiments, the gate electrode is configured to support current flow through the active region along a first direction, and a tensile stress layer covers the gate electrode and is configured to apply a tensile stress to the gate electrode along a second direction perpendicular to the first direction. The tensile stress layer may cover the recessed isolation region and portions of the active region between the isolation region and the gate electrode. In further embodiments, an interlayer insulating film is disposed on the tensile stress layer and is configured to apply a tensile stress to the gate electrode along the second direction.Type: ApplicationFiled: May 23, 2007Publication date: January 31, 2008Inventors: Dong-suk Shin, Andrew Tae Kim, Yong-kuk Jeong
-
Publication number: 20070272984Abstract: Provided is a semiconductor device manufacturing method including a field oxide insulation film forming step including forming a field oxide insulation film (12) so that, in an active region (13), a portion (13a), which corresponds to a side surface portion of the active region (13) opposing a rotation center (O) in spin-coating on the surface of the semiconductor substrate (11) in a centrifugal force acting direction (F) along the surface of the semiconductor substrate (11) and located in a forward side of the centrifugal force acting direction (F), has a curved surface convex to the forward side of the centrifugal force acting direction (F) when the semiconductor substrate (11) is seen in a plan view.Type: ApplicationFiled: May 21, 2007Publication date: November 29, 2007Inventors: Akiko Tsukamoto, Hisashi Hasegawa, Jun Osanai
-
Patent number: 7179702Abstract: A semiconductor device comprises a semiconductor substrate, an N-channel MISFET and a P-channel MISFET provided on the semiconductor substrate, each of the N- and P-channel MISFETs being isolated by an isolation region and having a gate insulating film, a first gate electrode film provided on the gate insulating film of the N-channel MISFET and composed of a first metal silicide, a second gate electrode film provided on the gate insulating film of the P-channel MISFET and composed of a second metal silicide made of a second metal material different from a first metal material composing the first metal silicide, and a work function of the first gate electrode film being lower than that of the second gate electrode film.Type: GrantFiled: September 23, 2005Date of Patent: February 20, 2007Assignee: Kabushiki Kaisha ToshibaInventor: Kouji Matsuo
-
Patent number: 7005716Abstract: Methods for forming dual-metal gate CMOS transistors are described. An NMOS and a PMOS active area of a semiconductor substrate are separated by isolation regions. A metal layer is deposited over a gate dielectric layer in each active area. Silicon ions are implanted into the metal layer in one active area to form an implanted metal layer which is silicided to form a metal silicide layer. Thereafter, the metal layer and the metal silicide layer are patterned to form a metal gate in one active area and a metal silicide gate in the other active area wherein the active area having the gate with the higher work function is the PMOS active area. Alternatively, both gates may be metal silicide gates wherein the silicon concentrations of the two gates differ. Alternatively, a dummy gate may be formed in each of the active areas and covered with a dielectric layer. The dielectric layer is planarized thereby exposing the dummy gates. The dummy gates are removed leaving gate openings to the semiconductor substrate.Type: GrantFiled: May 25, 2004Date of Patent: February 28, 2006Assignee: Chartered Semiconductor Manufacturing Ltd.Inventors: Wenhe Lin, Mei-Sheng Zhou, Kin Leong Pey, Simon Chooi
-
Patent number: 6992916Abstract: A high resistor SRAM memory cell to reduce soft error rate includes a first inverter having an output as a first memory node, and a second inverter having an output as a second memory node. The second memory node is coupled to an input of the first inverter through a first resistor. The first memory node is coupled to an input of the second inverter through a second resistor. A pair of access transistors are respectively coupled to a pair of bit lines, a split word line and one of the memory nodes. The resistors are prepared by coating a layer of silicide material on a selective portion of the gate structure of the transistors included in the first inverter, and connecting a portion of the gate structure that is substantially void of the silicide material to the drain of the transistors included in the second inverter.Type: GrantFiled: June 13, 2003Date of Patent: January 31, 2006Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.Inventor: Jhon-Jhy Liaw
-
Patent number: 6963111Abstract: A pMOS transistor (601) is located in an n-well (602) and has at least one gate (603). Transistor (601) is connected between power pad Vdd or I/O pad (604) and ground potential Vss (605). Gate (603) is connected to power pad (604). The n-well (602) is capacitively (620) coupled to ground (605), decoupled from the transistor source (606) and floating under normal operating conditions. Under an ESD event, the diode formed by the source (606) and the n-well (602) is forward biased (n-well negatively biased) to turn on the lateral pnp transistor to discharge the ESD current. The well voltage keeps increasing up to the value that triggers the lateral bipolar pnp transistor. The ESD protection is scalable with the width of gate (603), improving with shrinking gate width.Type: GrantFiled: June 13, 2003Date of Patent: November 8, 2005Assignee: Texas Instruments IncorporatedInventors: Vijay K. Reddy, Gianluca Boselli, Ekanayake A. Amerasekera
-
Patent number: 6940132Abstract: A semiconductor device includes a semiconductor substrate having a first major surface and a second major surface, source and drain layers formed in the first major surface, a gate insulating film formed on the first major surface, a gate layer formed on the gate insulating film, a source electrode formed on the first major surface and electrically connected to the source layer, a drain electrode formed on the first major surface, electrically connected to the drain layer, and having a second isolation portion, a gate electrode formed on the first major surface, electrically connected to the gate layer, and having a first isolation portion, a first capacitance adjusting electrode formed on the gate insulating film and having a first capacitance adjusted by the first isolation portion, and a second capacitance adjusting electrode formed on the gate insulating film and having a second capacitance adjusted by the second isolation portion.Type: GrantFiled: April 30, 2003Date of Patent: September 6, 2005Assignee: Kabushiki Kaisha ToshibaInventor: Kouji Kikuchi
-
Patent number: 6894365Abstract: A resistance element of a semiconductor device includes a first resistance pattern and a second resistance pattern formed adjacent to the first resistance pattern at a lower level, wherein the second resistance pattern is defined by the first resistance pattern in a self-aligned relationship and connected to the first resistance pattern in series.Type: GrantFiled: November 1, 1999Date of Patent: May 17, 2005Assignee: Ricoh Company, Ltd.Inventor: Yoshinori Ueda
-
Patent number: 6878579Abstract: An aspect of the present invention includes a first conductive type semiconductor region; a gate electrode formed on the first conductive type semiconductor region; a channel region formed immediately below the gate electrode in the first conductive type semiconductor region; and a second conductive type first diffusion layer constituting source/drain regions formed at opposite sides of the channel region in the first conductive type semiconductor region, the gate electrode being formed of polycrystalline silicon-germanium, in which a germanium concentration is continuously increased from a drain region side to a source region side, and an impurity concentration immediately below the gate electrode in the first conductive type semiconductor region being continuously increased from the source region side to the drain region side in accordance with the germanium concentration in the gate electrode.Type: GrantFiled: August 13, 2004Date of Patent: April 12, 2005Assignee: Kabushiki Kaisha ToshibaInventors: Kazuya Ohuchi, Hironobu Fukui
-
Patent number: 6870229Abstract: The present invention relates to an ultra-low power (ULP) MOS diode. The diode has a first and a second terminal. It comprises an n-MOS transistor having a channel, a first N+ doped diffusion region at one extremity of the channel and a second N+ diffusion region at the other extremity of the channel, and a p-MOS transistor having a channel and a first P+ doped diffusion region at one extremity of the channel and a second P+ diffusion region at the other extremity of the channel. The first N+ diffusion region of the n-MOS transistor is coupled to the first P+ diffusion region of the p-MOS transistor, the gate of the n-MOS transistor is coupled to the second P+ diffusion region of the p-MOS transistor, and the gate of the p-MOS transistor is coupled to the second N+ diffusion region of the n-MOS transistor.Type: GrantFiled: June 23, 2003Date of Patent: March 22, 2005Assignee: Universite Catholique de LouvainInventors: Vincent Dessard, Stéphane Adriaensen, Denis Flandre, David Levacq
-
Patent number: 6870224Abstract: When polycrystalline silicon germanium film is used for gate electrodes in a MOS transistor apparatus, there have been problems of reduced reliability in the gate insulating film, due to stress in the silicon germanium grains. Therefore, a polysilicon germanium film is formed, after forming silicon fine particles of particle size 10 nm or less on an oxide film. As a result, it is possible to achieve a high-speed MOS transistor apparatus using an ultra-thin oxide film having a film thickness of 1.5 nm or less, wherein the Ge concentration of the polycrystalline silicon germanium at its interface with the oxide film is uniform, thereby reducing the stress in the film, and improving the reliability of the gate electrode.Type: GrantFiled: August 15, 2003Date of Patent: March 22, 2005Assignee: Hitachi, Ltd.Inventors: Naoki Kanda, Arito Ogawa, Eisuke Nishitani, Miwako Nakahara, Tadanori Yoshida, Kiyoshi Ogata
-
Patent number: 6858908Abstract: A method of forming a first and second transistor. The method provides a semiconductor surface (20). The method also forms a gate dielectric (30) adjacent the semiconductor surface. Further, the method forms a first transistor gate electrode (902) comprising a metal portion (402) in a fixed relationship with respect to the gate dielectric. Still further, the method forms a second transistor gate electrode (901) comprising a silicide (701) of the metal portion in a fixed relationship with respect to the gate dielectric.Type: GrantFiled: August 13, 2003Date of Patent: February 22, 2005Assignee: Texas Instruments IncorporatedInventors: Antonio L. P. Rotondaro, Mark R. Visokay
-
Patent number: 6838747Abstract: A dopant is ion-implanted into a second region (52) of a polycrystalline silicon film (50) for a resistive element (5). Nitrogen or the like is ion-implanted into a second region (62) of a polycrystalline silicon film (60) for a resistive element (6). The density of crystal defects in the second regions (52, 62) is higher than that in first regions (51, 61). The density of crystal defects in a polycrystalline silicon film (70) for a resistive element (7) is higher near a silicide film (73). A polycrystalline silicon film (80) for a resistive element (8) is in contact with a substrate (2) with a silicide film in an opening of an isolation insulating film (3). The density of crystal defects in a substrate surface (2S) near the silicide film is higher than that in the vicinity. With such a structure, a current leak in an isolation region can be reduced.Type: GrantFiled: July 11, 2002Date of Patent: January 4, 2005Assignee: Renesas Technology Corp.Inventor: Hidekazu Oda
-
Patent number: 6791106Abstract: An aspect of the present invention includes a first conductive type semiconductor region; a gate electrode formed on the first conductive type semiconductor region; a channel region formed immediately below the gate electrode in the first conductive type semiconductor region; and a second conductive type first diffusion layer constituting source/drain regions formed at opposite sides of the channel region in the first conductive type semiconductor region, the gate electrode being formed of polycrystalline silicon-germanium, in which a germanium concentration is continuously increased from a drain region side to a source region side, and an impurity concentration immediately below the gate electrode in the first conductive type semiconductor region being continuously increased from the source region side to the drain region side in accordance with the germanium concentration in the gate electrode.Type: GrantFiled: April 23, 2003Date of Patent: September 14, 2004Assignee: Kabushiki Kaisha ToshibaInventors: Kazuya Ohuchi, Hironobu Fukui
-
Patent number: 6787850Abstract: The invention concerns a semi-conductor device comprising on a substrate: a first dynamic threshold voltage MOS transistor (10), with a gate (116), and a channel (111) of a first conductivity type, and a current limiter means (20) connected between the gate and the channel of said first transistor. In accordance with the invention, this first transistor is fitted with a first doped zone (160) of the first conductivity type, connected to the channel, and the current limiter means comprises a second doped zone (124) of a second conductivity type, placed against the first doped zone and electrically connected to the first zone by an ohmic connection. Application to the manufacture of CMOS circuits.Type: GrantFiled: July 27, 2001Date of Patent: September 7, 2004Assignee: Commissariat a l'Energie AtomiqueInventor: Jean-Luc Pelloie
-
Publication number: 20040140508Abstract: A method for fabricating a semiconductor device includes the steps of: forming a first insulating film on a semiconductor substrate; removing part of the first insulating film; forming a second insulating film having a leakage current density higher than that of the first insulating film on a region where the part of the first insulating film has been removed on the semiconductor substrate; forming an undoped semiconductor film on the first and second insulating films; implanting an impurity into part of the undoped semiconductor film, thereby defining semiconductor regions of a first conductivity type dotted as discrete islands; forming a third insulating film on the semiconductor regions of the first conductivity type and the undoped semiconductor film; and removing part of the third insulating film by wet etching. At least the second insulating film is formed under the semiconductor regions of the first conductivity type.Type: ApplicationFiled: January 8, 2004Publication date: July 22, 2004Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.Inventors: Naohisa Sengoku, Michikazu Matsumoto
-
Patent number: 6750519Abstract: Methods for forming dual-metal gate CMOS transistors are described. An NMOS and a PMOS active area of a semiconductor substrate are separated by isolation regions. A metal layer is deposited over a gate dielectric layer in each active area. Silicon ions are implanted into the metal layer in one active area to form an implanted metal layer which is silicided to form a metal silicide layer. Thereafter, the metal layer and the metal silicide layer are patterned to form a metal gate in one active area and a metal silicide gate in the other active area wherein the active area having the gate with the higher work function is the PMOS active area. Alternatively, both gates may be metal silicide gates wherein the silicon concentrations of the two gates differ. Alternatively, a dummy gate may be formed in each of the active areas and covered with a dielectric layer. The dielectric layer is planarized thereby exposing the dummy gates. The dummy gates are removed leaving gate openings to the semiconductor substrate.Type: GrantFiled: October 8, 2002Date of Patent: June 15, 2004Assignee: Chartered Semiconductor Manufacturing Ltd.Inventors: Wenhe Lin, Mei-Sheng Zhou, Kin Leong Pey, Simon Chooi
-
Publication number: 20040104438Abstract: An electronic structure that has in-situ formed unit resistors and a method for fabricating such structure are disclosed. The electronic structure that has in-situ formed unit resistors consists of a first plurality of conductive elements formed in an insulating material layer, a plurality of electrically resistive vias formed on top and in electrical communication with at least one of the first plurality of conductive elements, and a second plurality of conductive elements formed on top of and in electrical communication with at least one of the plurality of electrically resistive vias. The present invention novel structure may further be formed in a multi-level configuration such that multi-level resistors may be connected in-series to provide larger resistance values. The present invention novel structure may further be combined with a capacitor network to form desirable RC circuits.Type: ApplicationFiled: November 10, 2003Publication date: June 3, 2004Applicant: International Business Machines CorporationInventors: Cyril Cabral, Lawrence Clevenger, Louis Lu-Chen Hsu, Keith Kwong Hon Wong
-
Patent number: 6670683Abstract: A metal oxide semiconductor transistor having a slew-rate control is disclosed. The transistor having a slew-rate control includes an elongated diffusion area and an elongated gate overlying the diffusion area. The elongated diffusion area has at least two diffusion regions, each having a threshold voltage that is different from each other. The elongated gate has a gate contact at only one side of the elongated diffusion area.Type: GrantFiled: January 4, 2001Date of Patent: December 30, 2003Assignee: International Business Machines CorporationInventors: Kerry Bernstein, Anthony Correale, Jr., Terence Blackwell Hook, Douglas Willard Stout
-
Patent number: 6646309Abstract: Employing an electrostatic discharge (ESD) trigger to trigger the MOS transistors (i.e., the ESD fingers) within a CMOS device to provide substantially more uniform turn-on voltages for the MOS transistors, resulting in better ESD device performance without employing selective salicide blocking, is disclosed. A semiconductor device has an ESD trigger and a number of ESD fingers. The turn on voltage of the ESD trigger is less than the turn on voltage of the ESD fingers, such that the ESD fingers turn on substantially uniformly after the ESD trigger turns on during an ESD event. The semiconductor device is substantially fabricated without employing salicide blocking.Type: GrantFiled: October 17, 2002Date of Patent: November 11, 2003Assignee: Taiwan Semiconductor Manufacturing Co. Ltd.Inventor: Chung-Hui Chen
-
Patent number: 6646324Abstract: A method and apparatus for a linearized output driver and terminator is described. In one embodiment the method includes forming a gate electrode on a substrate, the portion of the substrate covered by the gate electrode defining a channel. The method further includes forming a first source/drain doped region on laterally opposed sides of the gate electrode in the substrate. The method also includes forming a spacer on laterally opposed sides of the gate electrode on the substrate. The method also includes forming a linearized drain contact region at a location within the first source/drain doped region sufficiently distant from the gate electrode to define a series resistor in the first source/drain doped region disposed between the gate electrode and the linearized drain contact area based on an expected resistivity of the source/drain doped region, the series resistor coupled electrically to the channel.Type: GrantFiled: June 30, 2000Date of Patent: November 11, 2003Assignee: Intel CorporationInventors: Sanjay Dabral, Krishna Seshan
-
Patent number: 6627957Abstract: To provide a semiconductor device restraining high frequency impedance and restraining deterioration of a semiconductor layer, a gate wiring 26 is extended while meandering and intersects with a substantially straight line portion of a semiconductor layer 02 by a plurality of times thereby providing a plurality of gates.Type: GrantFiled: June 8, 1999Date of Patent: September 30, 2003Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventor: Shunpei Yamazaki
-
Patent number: 6617632Abstract: A parallel connection-type nonvolatile memory semiconductor device comprises a plurality of memory cells disposed on a semiconductor substrate in matrix form, each including a gate insulating film, a floating gate electrode, an interlayer film and a control gate electrode successively formed so as to cover a channel region on a main surface of the semiconductor substrate, of a first conductivity type; a second conductivity type source and drain regions formed on the semiconductor substrate on both sides opposite to each other, of the floating gate electrode so as to interpose a channel region located under the floating gate electrode therebetween; a first semiconductor region which is adjacent to the drain region and formed by introducing a second conductivity type impurity in the direction of the channel region placed under the floating gate electrode from an end on the drain side, of the floating gate electrode, and which is substantially lower than the drain region in impurity concentration; and a punch-thType: GrantFiled: December 7, 2001Date of Patent: September 9, 2003Assignee: Hitachi, Ltd.Inventors: Yasuhiro Taniguchi, Kazuyoshi Shiba, Nozomu Matsuzaki, Hidenori Takada, Hitoshi Kume, Shoji Shukuri
-
Patent number: 6614061Abstract: The present invention provides an electrostatic discharge-protection device located between a pad and a specific voltage point. The electrostatic discharge-protection device has a P-type substrate. Then a first N-type well, a first P-type doped region, and a first N-type doped region, are formed on the P-type substrate, wherein the first P-type doped region and the first N-type doped region are coupled to the specific voltage point, respectively. A second P-type doped region and a second N-type doped region are formed on the first N-type well and are coupled to the pad, respectively. Moreover, a third N-type doped region and a fourth N-type doped region are formed on the P-type substrate. The third N-type doped region is coupled to the pad, and a second N-type well is formed between the third N-type doped region and the fourth N-type doped region.Type: GrantFiled: February 13, 2001Date of Patent: September 2, 2003Assignee: Windbond Electronics Corp.Inventor: Jiunn-Way Miaw
-
Patent number: 6580108Abstract: An insulated gate transistor comprising a first semiconductor region, a second semiconductor region includes plural portions, a third semiconductor region, a fourth semiconductor region, a first insulation layer, control electrodes, a first main electrode, and a second main electrode, wherein a metallic wiring layer is provided on the first main surface plane via an insulating layer, plural regions insulated from the first main electrode are provided through said first main electrode, and the metallic wiring layer is connected electrically to the control electrode through the insulating layer via the region insulated from the main electrode.Type: GrantFiled: February 3, 2000Date of Patent: June 17, 2003Assignees: Hitachi, Ltd., Hitachi Haramachi Electronics Co., Ltd.Inventors: Tomoyuki Utsumi, Shoichi Ozeki, Koichi Suda
-
Patent number: 6566717Abstract: An electrostatic discharge (ESD) protection circuit for protecting an internal device from an ESD is disclosed. The ESD protection circuit includes an NMOS transistor connected to a ground voltage terminal having silicide layers on a gate electrode and on source/drain regions thereof; and a PMOS transistor having a gate electrode connected to a ground voltage terminal and connecting the NMOS transistor to a pad.Type: GrantFiled: September 7, 2001Date of Patent: May 20, 2003Assignee: Hynix Semiconductor Inc.Inventor: Jong-Chuck Jung
-
Patent number: 6521943Abstract: Disclosed is a semiconductor device (e.g., nonvolatile semiconductor memory device) and method of forming the device. The device includes a gate electrode (e.g., floating gate electrode) having a first layer of an amorphous silicon film, or a polycrystalline silicon thin film or a film of a combination of amorphous and polycrystalline silicon, on the gate insulating film. Where the film includes polycrystalline silicon, the thickness of the film is less than 10 nm. A thicker polycrystalline silicon film can be provided on or overlying the first layer. The memory device can increase the write/erase current significantly without increasing the low electric field leakage current after application of stresses, which in turn reduces write/erase time substantially.Type: GrantFiled: March 7, 2000Date of Patent: February 18, 2003Assignee: Hitachi, Ltd.Inventors: Toshiyuki Mine, Jiro Yugami, Takashi Kobayashi, Masahiro Ushiyama
-
Patent number: 6507072Abstract: In an insulated gate field effect semiconductor device, the gate electrode formed on the gate insulating film includes the first and second semiconductor layers as a double layer. An impurity for providing one conductivity type is not contained in first semiconductor layer which is in contact with a gate insulating film and is contained at a high concentration in the second semiconductor layer which is not in contact with the gate insulating film. Accordingly, By existence of the first semiconductor layer is which the impurity is not doped, the impurity is prevented from penetrating through the gate insulating film from the gate electrode and diffusing into the channel forming region. Also, by existence of the second semiconductor layer in which high concentration impurity is doped, the gate electrode has low resistance.Type: GrantFiled: June 29, 2001Date of Patent: January 14, 2003Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventor: Yukio Yamauchi
-
Patent number: 6469351Abstract: A Vss-side off transistor is often used in an electrostatic breakdown prevention circuit having an NMOS transistor. In such a circuit, the state of connection of the transistor ensures that off-leak current has a significant influence on the standby current, which is particularly noticeable when the circuit is used in a semiconductor device running at low power consumption. In such case, since the threshold voltage of a MOS transistor forming the semiconductor device is made as low as possible, the sub-threshold leak current in the electrostatic breakdown prevention circuit is large. To prevent this, the NMOS transistor forming the electrostatic breakdown prevention circuit is formed with a P type gate electrode for the purpose of increasing its threshold voltage by about 1.1 V as compared with that if the gate electrode of the NMOS transistor were to have an N type gate electrode.Type: GrantFiled: June 1, 1999Date of Patent: October 22, 2002Assignee: Seiko Instruments Inc.Inventor: Yoichi Mimuro
-
Publication number: 20020149064Abstract: Polysilicon electrical depletion in a polysilicon gate electrode is reduced by depositing the polysilicon under controlled conditions so as to vary the crystal grain size through the thickness of the polysilicon. The resulting structure may have two or more depth-wise contiguous regions of respective crystalline grain size, and the selection of grain size is directed to maximize dopant activation in the polysilicon near the gate dielectric, and to tailor the resistance of the polysilicon above that first region and more distant from the gate dielectric. This method, and the resulting structure, are advantageously employed in forming FETs, and doped polysilicon resistors.Type: ApplicationFiled: March 10, 2001Publication date: October 17, 2002Inventors: Arne W. Ballantine, Kevin K. Chan, Jeffrey D. Gilbert, Kevin M. Houlihan, Glenn L. Miles, James J. Quinlivan, Samuel C. Ramac, Michael B. Rice, Beth A. Ward
-
Patent number: 6455883Abstract: A source region and a drain region are formed in a silicon substrate, a dielectric film is formed above a region of the silicon substrate between the source region and the drain region, a ferroelectric film is formed on the dielectric film, and a gate electrode is formed on the ferroelectric film. The ferroelectric film and the silicon substrate have a first conductivity type, and the source region and the drain region has a second conductivity type.Type: GrantFiled: June 13, 2001Date of Patent: September 24, 2002Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Yoshihisa Kato, Yasuhiro Shimada
-
Publication number: 20010035541Abstract: The invention encompasses stacked semiconductor devices including gate stacks, wordlines, PROMs, conductive interconnecting lines, and methods for forming such structures. The invention also includes a method of forming a transistor gate comprising: a) forming gate dielectric layer; b) forming a polysilicon gate layer against the gate dielectric layer; and c) doping the polysilicon gate layer with a conductivity-enhancing dopant, the dopant being provided in a concentration gradient within the polysilicon layer, the concentration gradient increasing in a direction toward the gate dielectric layer. The invention also includes a wordline comprising: a) a polysilicon line; a substantially fluorine impervious barrier layer over the polysilicon line; and a b) layer of metal-silicide over the substantially fluorine impervious barrier layer.Type: ApplicationFiled: June 11, 2001Publication date: November 1, 2001Inventors: Klaus Florian Schuegraf, Carl Powell, Randhir P. S. Thakur
-
Patent number: 6300660Abstract: A variable conductance device having a first source region and a first drain region in a semiconductor substrate. A first channel region connects the first source and the first drain regions. A first resistive layer overlies the first channel region and has first and second electrical contacts spaced apart from one another thereon. The conductance of the path between the first source region and the first drain region depends on the current flowing between the first and second electrical contacts. By adding a FET having its gate and source shorted together to the variable conductance device, a device having the current gain characteristics of a bipolar transistor is obtained. The first drain region is connected to the drain of the FET and the source of the FET is connected to the second electrical contact. The precise form of the current transfer function can be altered by connecting a number of variable conductance devices according to the present invention in parallel.Type: GrantFiled: December 31, 1999Date of Patent: October 9, 2001Inventor: Robert Patti
-
Patent number: 6259141Abstract: In an insulated gate field effect semiconductor device, the gate electrode formed on the gate insulating film includes the first and second semiconductor layers as a double layer. An impurity for providing one conductivity type is not contained in first semiconductor layer which is in contact with a gate insulating film and is contained at a high concentration in the second semiconductor layer which is not in contact with the gate insulating film. Accordingly, by existence of the first semiconductor layer is which the impurity is not doped, the impurity is prevented from penetrating through the gate insulating film from the gate electrode and diffusing into the channel forming region. Also, by existence of the second semiconductor layer in which high concentration impurity is doped, the gate electrode has low resistance.Type: GrantFiled: November 15, 1999Date of Patent: July 10, 2001Assignee: Semiconductor Energy Labortary Co., Ltd.Inventor: Yukio Yamauchi
-
Patent number: 6236088Abstract: An arrangement for providing thermal overload protection for a gated electrode power semiconductor device comprises connecting the gate electrode of the device in a series circuit between the gate electrode terminal applying a bias voltage to the gate electrode and the source region adjoining the channel region controlled by the gate electrode. The series circuit includes an electrical resistor, preferably the gate electrode itself, and a temperature sensitive element blocking current flow through the gate electrode at safe operating temperatures, but allowing current flow, for de-biasing the gate electrode by IR drop through the resistor, when excessive device temperatures are sensed. The temperature sensitive element preferably comprises a reverse biased junction or Schottky barrier formed within the gate electrode.Type: GrantFiled: June 23, 1999Date of Patent: May 22, 2001Assignee: Intersil CorporationInventors: John Manning Savage Nielson, Donald E. Burke, Blake Andrew Gillett
-
Patent number: 6218689Abstract: The present invention provides a method and a NAND-type flash memory device. The method includes forming a select gate oxide layer in a select transistor area of a substrate and a tunnel oxide layer in a memory cell area of the substrate; forming a doped amorphous silicon layer on the select gate oxide layer and the tunnel oxide layer, the doped amorphous silicon layer having a dopant level which simultaneously avoids a select transistor word line high resistance problem and a charge gain/charge loss problem; forming an insulating layer on the doped amorphous silicon layer; forming a control gate layer on the insulating layer; and etching at least the doped amorphous silicon layer, the insulating layer, and the control gate layer to form at least one memory cell stack structure and at least one select transistor stack structure.Type: GrantFiled: August 6, 1999Date of Patent: April 17, 2001Assignee: Advanced Micro Devices, Inc.Inventors: Kent Kuohua Chang, Kenneth Wo-Wai Au, Hao Fang
-
Patent number: 6211531Abstract: A controllable conduction device in the form of a transistor comprises source and drain regions 5, 2 between which extends a conduction path P for charge carriers, a gate 4 for controlling charge carrier flow along the conduction path and a multiple layer structure 3 providing a multiple tunnel junction configuration in the conduction path, with the result that current leakage is blocked by the multiple tunnel junction configuration when the transistor is in its off state. Vertical and lateral transistor configurations are described, together with use of the transistor in complimentary pairs and for a random access memory cell. Improved gate structures are described which are also applicable to memory devices that incorporate the tunnel barrier configuration to store charge on the memory node.Type: GrantFiled: January 27, 2000Date of Patent: April 3, 2001Assignee: Hitachi, Ltd.Inventors: Kazuo Nakazato, Kiyoo Itoh, Hiroshi Mizuta, Toshikazu Shimada, Hideo Sunami, Tatsuya Teshima, Toshiyuki Mine, Ken Yamaguchi
-
Patent number: 6091118Abstract: A semiconductor device and process for manufacture thereof is disclosed in which a gate electrode with reduced overlap capacitance is formed by forming a gate electrode on a surface of a semiconductor and doping edge portions of the gate electrode with a first doping which effectively reduces the conductivity of the edge portions of the gate electrode. The conductivity of the gate electrode may be reduced at the edge portions by doping the edge portions with a dopant which inhibits the doping of the gate electrode or with a dopant which has a different conductivity type than the gate electrode dopant.Type: GrantFiled: June 24, 1998Date of Patent: July 18, 2000Assignee: Advanced Micro Devices, Inc.Inventor: Michael Duane
-
Patent number: 6051856Abstract: An improved FET for use as a voltage-controlled resistor includes a p-type control gate and a high-resistance connection to receive a control signal. The bootstrap frequency for the device is much lower than the signal frequency so that the signal frequency is decoupled from the control voltage to reduce distortion.Type: GrantFiled: September 30, 1997Date of Patent: April 18, 2000Assignee: Samsung Electronics Co., Ltd.Inventors: Thomas G. McKay, Joseph Barrera
-
Patent number: 6028339Abstract: A dual work function CMOS device and method for producing the same is disclosed. The method includes: depositing a first layer of a doped material, either n-type or p-type, over a substrate to be doped; defining the areas that are to be oppositely doped; depositing a second layer of an oppositely doped material over the entire surface; and subjecting the entire CMOS device to a high temperature, drive-in anneal. The drive-in anneal accelerates the diffusion of the dopants into the adjacent areas, thereby doping the gate polysilicon and channels with the desired dopants. A nitride barrier layer may be utilized to prevent the second dopant from diffusing through the first layer and into the substrate beneath.Type: GrantFiled: December 14, 1998Date of Patent: February 22, 2000Assignee: International Business Machines CorporationInventors: Robert O. Frenette, Dale P. Hallock, Stephen A. Mongeon, Anthony C. Speranza, William R. P. Tonti
-
Patent number: 5998842Abstract: A MOS semiconductor device with control electrodes for improved switching accuracy and operational speeds of the device at reduced power consumption levels. The semiconductor device includes a substrate, a source electrode region and a drain electrode region formed in said substrate, a first gate insulating film formed on said substrate, a semiconductor region formed on said first gate insulating film, a second gate insulating film formed on said semiconductor region, a gate electrode region formed on said second gate insulating film, and at least one control electrode region disposed in contact with said semiconductor region.Type: GrantFiled: July 23, 1996Date of Patent: December 7, 1999Assignee: Ricoh Company, Ltd.Inventor: Yutaka Sano
-
Patent number: 5894157Abstract: A method for fabricating a MOS transistor having an offset resistance in a channel region controlled by a gate voltage and structure thereof is disclosed. A gate electrode is divided into three adjacent regions of respectively a second conductivity type, first conductivity type and second conductivity type connected laterally to one another on a channel region. A gate control voltage is applied to a central region of the first conductivity type, and a predetermined voltage between maximum and minimum values of the gate control voltage is applied to left and right adjacent regions of the second conductivity type. If a gate turn-on voltage is applied to the central region the gate turn-on voltage is forward biased to the adjacent left and right regions and is therefore also applied to the forwardly biased left and right regions. The effective length of the gate electrode then becomes the total length of the central region and the left and right adjacent regions.Type: GrantFiled: June 27, 1994Date of Patent: April 13, 1999Assignee: Samsung Electronics Co., Ltd.Inventors: Min-Koo Han, Byung-Hyuk Min
-
Patent number: 5872372Abstract: A thin film transistor is disclosed comprising a piezoelectric film formed on a piezoresistive body of an ultra thin film and a gate electrode formed on the piezoelectric film. Due to the force generated from the piezoelectric film by an electric field generated according to the strength of a voltage applied to the gate electrode, a pressure is applied on the piezoresistive body to vary the resistance of the piezoresistive body. Thus, the quantity of current that flows from a source terminal through the piezoresistive channel to a drain terminal can be controlled. Since the piezoresistive body can be formed on a plane, a thin film transistor with a three-dimensional structure can be manufactured.Type: GrantFiled: September 11, 1996Date of Patent: February 16, 1999Assignee: Electronics and Telecommunications Research InstituteInventors: Seong-Jae Lee, Kyoung-Wan Park, Min-Cheol Shin
-
Patent number: 5844272Abstract: A high frequency MOS transistor structure with an extended drift region, which modulates the resistance in the drift region of the MOS transistor. The extended gate layer is obtained by an extra semiconductor layer forming a second MOS structure on top of a thin gate oxide layer. The electrical field will then be uniformly distributed laterally in the extended drift region. This design makes it possible to produce a MOS transistor with a short channel length and an extended drift region with low doping concentration and still having very low on-resistance together with a high breakdown voltage.Type: GrantFiled: July 25, 1997Date of Patent: December 1, 1998Assignee: Telefonaktiebolaet LM EricssonInventors: Anders Soderbarg, Per Svedberg
-
Patent number: 5814867Abstract: A semiconductor device includes a pair of transistors each having an active region defined on a surface of a semiconductor substrate, a gate insulation film formed on the active region, a gate electrode formed on the gate insulation film, and a diffusion layer formed in the active region of the semiconductor substrate, one of the transistors having an opening formed by removing part of the gate insulation film on the active region, through which opening the diffusion layer is directly connected to the gate electrode of the other transistor, an end portion of the gate electrode intersecting the outer periphery of the opening at at least one point on the diffusion layer.Type: GrantFiled: October 25, 1995Date of Patent: September 29, 1998Assignee: Sharp Kabushiki KaishaInventor: Satoshi Saito