Patents Examined by Scott Brairton
  • Patent number: 6756324
    Abstract: A thin film transistor is described incorporating a gate electrode, a gate insulating layer, a semiconducting channel layer deposited on top of the gate insulating layer, an insulating encapsulation layer positioned on the channel layer, a source electrode, a drain electrode and a contact layer beneath each of the source and drain electrodes and in contact with at least the channel layer, all of which are situated on a plastic substrate. By enabling the use of plastics having low glass transition temperatures as substrates, the thin film transistors may be used in large area electronics such as information displays and light sensitive arrays for imaging which are flexible, lighter in weight and more impact resistant than displays fabricated on traditional glass substrates. The thin film transistors are useful in active matrix liquid crystal displays where the plastic substrates are transparent in the visible spectrum.
    Type: Grant
    Filed: March 25, 1997
    Date of Patent: June 29, 2004
    Assignee: International Business Machines Corporation
    Inventor: Stephen McConnell Gates
  • Patent number: 6682961
    Abstract: A gate insulating layer, an amorphous silicon layer, an n+ amorphous silicon layer and a metal layer are deposited in sequence after a gate line, a gate electrode and a gate pad are formed on a substrate, using a first mask. The metal layer is etched to form a data line, a source electrode, a drain electrode and a data pad through a photolithography process, using a second mask, and the n+ amorphous silicon layer is etched, using the patterned data line, the source electrode, the drain electrode and the data pad as the mask. A light shielding film and a passivation film, or a passivation film also having a function of the light shielding film are deposited, and is etched through the photolithography process, using a third mask which leaves a portion covering the gate line, the gate electrode, the gate pad and the data line, the source electrode, and the drain electrode.
    Type: Grant
    Filed: September 17, 1998
    Date of Patent: January 27, 2004
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Dong-Gyu Kim
  • Patent number: 6599790
    Abstract: A laser-irradiation method which comprises a process for fabricating a semiconductor device, comprising: a first step of forming a thin film amorphous semiconductor on a substrate having an insulating surface; a second step of modifying the thin film amorphous semiconductor into a crystalline thin film semiconductor by irradiating a pulse-type linear light and/or by applying a heat treatment; a third step of implanting an impurity element which imparts a one conductive type to the crystalline thin film semiconductor; and a fourth step of activating the impurity element by irradiating a pulse-type linear light and/or by applying a heat treatment; wherein the peak value, the peak width at half height, and the threshold width of the laser energy in the second and the fourth steps above are each distributed within a range of approximately ±3% of the standard value. Also claimed is a laser irradiation device which realizes the method above.
    Type: Grant
    Filed: February 13, 1997
    Date of Patent: July 29, 2003
    Assignee: Semiconductor Energy Laboratory Co., Ltd
    Inventors: Shunpei Yamazaki, Satoshi Teramoto, Naoto Kusumoto, Takeshi Fukunaga, Setsuo Nakajima, Tadayoshi Miyamoto, Atsushi Yoshinouchi
  • Patent number: 6599791
    Abstract: In a monolithic active matrix circuit that uses offset-gate TFTs in which the gate electrode is offset from the source and drain regions or TFTs whose gate insulating film is formed by vapor deposition, not only an active matrix circuit but also a drive circuit therefor is formed by using P-channel TFTs.
    Type: Grant
    Filed: January 13, 1999
    Date of Patent: July 29, 2003
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Jun Koyama, Yuji Kawasaki
  • Patent number: 6472229
    Abstract: The purpose of this invention is to provide a method for manufacturing capacitors free of polarization fatigue even when the treatment is performed at a low temperature. Amorphous layer 32 made of lead zirconate titanate and containing excess lead is formed on lower electrode 13 made of iridium. The amorphous layer is crystallized by a heat treatment to form PZT film 14. Structural transition layer 33 containing excess Pb formed on the surface of PZT film 14 during the aforementioned crystallization is removed by means of dry etching. In this way, a PZT capacitor is obtained.
    Type: Grant
    Filed: June 5, 1998
    Date of Patent: October 29, 2002
    Assignee: Texas Instruments Incorporated
    Inventors: Katsuhiro Aoki, Yukio Fukuda, Ken Numata
  • Patent number: 6468837
    Abstract: A semiconductor device (10) comprises a reduced surface field (RESURF) implant (14). A field oxide layer (20), having a length, is formed over the RESURF implant (14). A field plate (12) extends from a near-side of the field oxide layer (20) and over at least one-half of the length of the field oxide layer (20).
    Type: Grant
    Filed: August 1, 2000
    Date of Patent: October 22, 2002
    Assignee: Texas Instruments Incorporated
    Inventors: Sameer P. Pendharkar, Taylor R. Efland
  • Patent number: 6465266
    Abstract: Semiconductor device analysis is improved through the distinguishing of gate oxide failures from other non-oxide failures. According to an example embodiment of the present invention, oxide failures are distinguished from non-oxide shorts between a gate and source/drain region in a semiconductor device during gate oxide analysis. An electrical characteristic that exhibits a first response to an oxide failure and a second response to a non-oxide failure is detected and used to detect the nature of a short in the device. This analysis is easily incorporated into other tests, such as the Voltage Ramp Dielectric Breakdown test (VRDB), and is particularly useful for improving the ability to detect and analyze defects without necessarily viewing the defect or destroying the device.
    Type: Grant
    Filed: January 5, 2001
    Date of Patent: October 15, 2002
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Abdullah Mohamad Yassine, Kola Olasupo
  • Patent number: 6455359
    Abstract: A laser-irradiation method which comprises a process for fabricating a semiconductor device, comprising: a first step of forming a thin film amorphous semiconductor on a substrate having an insulating surface; a second step of modifying the thin film amorphous semiconductor into a crystalline thin film semiconductor by irradiating a pulse-type linear light and/or by applying a heat treatment; a third step of implanting an impurity element which imparts a one conductive type to the crystalline thin film semiconductor; and a fourth step of activating the impurity element by irradiating a pulse-type linear light and/or by applying a heat treatment; wherein the peak value, the peak width at half height, and the threshold width of the laser energy in the second and the fourth steps above are each distributed within a range of approximately ±3% of the standard value. Also claimed is a laser irradiation device which realizes the method above.
    Type: Grant
    Filed: April 22, 1999
    Date of Patent: September 24, 2002
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Satoshi Teramoto, Naoto Kusumoto, Takeshi Fukunaga, Setsuo Nakajima, Tadayoshi Miyamoto, Atsushi Yoshinouchi
  • Patent number: 6451694
    Abstract: In a process for mitigating and/or eliminating the abnormal growth of underlying polysilicon in dichloro silane-based CVD polycide WSix films, a first technique conducts the deposition of the underlying polysilicon layer at a temperature that substantially avoids crystallization of the underlying polysilicon. A second approach reduces the exposure (for example time period and or concentration) of the mono-silane SiH4 post flush, so as to avoid infusion of silicon into the underlying polysilicon layer, and resulting abnormal growth. In this manner, abnormal effects, such as stress fractures formed in subsequent layers, can be eliminated.
    Type: Grant
    Filed: April 4, 2001
    Date of Patent: September 17, 2002
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jeon-Sig Lim, Jin-Ho Jeon, Jong-Seung Yi, Chul-Hwan Choi
  • Patent number: 6444509
    Abstract: The present invention pertains to a high-performance thin film transistor having a gate and an active region, whose active region comprises a poly-Si1−xGex alloy material and a channel layer of silicon, in which the channel layer of silicon is interposed between the poly-Si1−xGex alloy material and the gate, and a method for fabricating such a high-performance thin film transistor.
    Type: Grant
    Filed: December 23, 1997
    Date of Patent: September 3, 2002
    Assignees: Sony Corporation, Massachusetts Institute of Technology
    Inventors: Takashi Noguchi, Rafael Reif, Julie Tsai, Andrew J. Tang
  • Patent number: 6429050
    Abstract: The invention is a lead frame that has leads formed in two levels during the etching process in which the lead frame is formed. A lead frame form (40), or continuous strip of lead frame material, is coated on two sides with a photo resist material (41,43). Each photo resist coated side is patterned to define leads on the lead frame. The lead patterns (41,43, 42,44) on the two sides are offset from each other so that patterns on one side of the lead frame material alternate with the patterns on the other side of the lead frame material. Both sides of the photo resist patterned lead frame material are etched to a depth exceeding the thickness of a lead. The photo resist (41,43) material is then removed. The resulting lead frame has leads (50-56)that are in two levels, each level having leads offset by a lead width from the other level, but with an effective zero distance between leads horizontally.
    Type: Grant
    Filed: December 15, 1998
    Date of Patent: August 6, 2002
    Assignee: Texas Instruments Incorporated
    Inventors: Robert M. Fritzsche, Donald C. Abbott
  • Patent number: 6429100
    Abstract: A line beam is irradiated such that edge lines of the beam extend in a direction at an angle of 45° with respect to the vertical direction or the horizontal direction. As a result, a laser defective crystallization region R′ where the grain size has not become sufficiently large due to unevenness in intensity of the line beam passes at 45° across the carrier path connecting source and drain regions S and D to each other. The defective crystallization region R′ thus does not completely divide between the contact region CT, i.e., the carrier path between the source and drain regions. Therefore, a carrier path CP can be securely maintained without passing through the defective crystallization region R′, so that the ON-current is prevented from being reduced. Deterioration or unevenness in transistor characteristics caused by unevenness in intensity of laser irradiation can thus be prevented.
    Type: Grant
    Filed: May 29, 1997
    Date of Patent: August 6, 2002
    Assignee: Sanyo Electric Co., Ltd.
    Inventor: Kiyoshi Yoneda
  • Patent number: 6423586
    Abstract: A semiconductor material and a method for forming the same, said semiconductor material having produced by a process comprising melting a noncrystal semiconductor film containing therein carbon, nitrogen, and oxygen each at a concentration of 5×1019 atoms·cm−3 or lower, preferably 1×1019 atoms·cm−3 or lower, by irradiating a laser beam or a high intensity light equivalent to a laser beam to said noncrystal semiconductor film, and then recrystallizing the thus molten amorphous silicon film. The present invention provides thin film semiconductors having high mobility at an excellent reproducibility, said semiconductor materials being useful for fabricating thin film semiconductor devices such as thin film transistors improved in device characteristics.
    Type: Grant
    Filed: March 9, 1998
    Date of Patent: July 23, 2002
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Hongyong Zhang, Naoto Kusumoto, Yasuhiko Takemura
  • Patent number: 6406952
    Abstract: A process for device fabrication, comprising the steps of forming a dielectric material region on a silicon substrate, forming a first amorphous silicon or polysilicon region on the dielectric material region, implanting one or more dopants in the first amorphous silicon or polysilicon region, and, subsequent to implanting the one or more dopants in the first amorphous silicon or polysilicon region, forming a second amorphous silicon or polysilicon region on the first amorphous silicon or polysilicon region. Typically, a refractory metal silicide layer is formed over the silicon, and such silicide is optionally formed by a salicide process. The second silicon region makes it more difficult for the implanted dopants to reach the silicide layer, and thereby reduces undesirable lateral diffusion of dopants in the silicide and accompanying cross-doping. The buried nature of the dopants in the silicon further reduces the amount of lateral diffusion within the silicon, regardless of the gate material.
    Type: Grant
    Filed: July 29, 1997
    Date of Patent: June 18, 2002
    Assignee: Agere Systems Guardian Corp.
    Inventor: Joze Bevk
  • Patent number: 6406946
    Abstract: A TFT matrix-type liquid crystal display device is used in laptop personal computers and wall TV's. On a transparent insulating substrate there are formed gate bus lines for commonly connecting the gates of thin film transistors, drain bus lines for commonly connecting the drains of the thin film transistors, and outside terminals and outside terminals opposed respectively to the ends of the gate bus lines and the drain bus lines, opposed respectively to the ends of the gate bus lines and the drain bus lines. Gate connection lines for commonly connecting the gate bus lines and drain connection lines for commonly connecting the drain bus lines are formed on the transparent insulating substrate in regions inner of the outside terminals. The thin film transistor matrix device can be fabricated without occurrence of short circuit defects, with little characteristic change and with high yields.
    Type: Grant
    Filed: January 8, 1998
    Date of Patent: June 18, 2002
    Assignee: Fujitsu Limited
    Inventors: Hidaki Takizawa, Shougo Hayashi, Takeshi Kinjo, Makoto Tachibanaki, Kenji Okamoto
  • Patent number: 6395567
    Abstract: A method of detecting defects on dice in semiconductor wafer wherein each dice in a layer is scanned and data from each dice is compared to data collected from an ideal dice obtained from the same level on a pre-production wafer. The data from each dice is compared in an optical comparator with data from the ideal dice stored in a register.
    Type: Grant
    Filed: July 2, 1998
    Date of Patent: May 28, 2002
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Paul J. Steffan, Allen S. Yu
  • Patent number: 6391694
    Abstract: In a source/drain doping step in manufacturing a field effect transistor, particularly a thin-film transistor (TFT), high-speed boron ions are implanted in a state that an active layer in which to form the source and drain is covered with an insulating film, whereas phosphorus ions are implanted in a state that the surface of the active layer is exposed.
    Type: Grant
    Filed: February 25, 1999
    Date of Patent: May 21, 2002
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hongyong Zhang, Hideto Ohnuma, Yasuhiko Takemura
  • Patent number: 6372611
    Abstract: In a method of manufacturing a semiconductor device, a first polysilicon film is formed on a surface of a semiconductor substrate for a semiconductor element to be formed thereon. Ion implantation is performed in such a manner that impurity ions are implanted into the semiconductor substrate surface through the first polysilicon film. The semiconductor substrate is heated to a first temperature after the step of performing ion implantation. Then, the semiconductor substrate is gradually cooled with a predetermined cooling rate at least from a second temperature to a third temperature while the semiconductor substrate is cooled from the first temperature. The second and third temperatures are lower than the first temperature. Subsequently, the polysilicon film is removed after the gradually cooling step.
    Type: Grant
    Filed: January 14, 1998
    Date of Patent: April 16, 2002
    Assignee: NEC Corporation
    Inventor: Mitsuhiro Horikawa
  • Patent number: 6372592
    Abstract: A method for making a self-aligned FET with an electrically active mask comprises the steps of forming a semiconductor layer on an insulating substrate, forming an electrically nonconductive oxide layer on the semiconductor layer, forming an electrically conductive metal layer on the oxide layer, patterning the metal layer and the oxide layer to form an electrically active gate on semiconductor layer, introducing dopants into the semiconductor layer to form a source region and a drain region masked by the metal gate, and illuminating the source and the drain regions with a pulsed excimer laser having a wavelength from about 150 nm to 350 nm to anneal the source region and the drain region.
    Type: Grant
    Filed: December 18, 1996
    Date of Patent: April 16, 2002
    Assignee: United States of America as represented by the Secretary of the Navy
    Inventors: Stephen D. Russell, Douglas A. Sexton, Bruce W. Offord, George P. Imthurn
  • Patent number: 6358828
    Abstract: A three-dimensional integrated circuit and fabrication process is provided for producing active and passive devices on various levels of the integrated circuit. The present process is particularly suited to interconnecting a source of one transistor to a drain of another to form series-connected transistors often employed in core logic units. A junction of an underlying transistor can be connected to a junction of an overlying transistor, with both transistors separated by an interlevel dielectric. The lower transistor junction is connected to the upper level transistor junction using a plug conductor. The plug conductor and, more specifically, the mutually connected junction, is further coupled to a laterally extended interconnect. The interconnect extends from the mutual connection point of the plug conductor to a substrate of the overlying transistor.
    Type: Grant
    Filed: July 17, 1998
    Date of Patent: March 19, 2002
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Daniel Kadosh, Mark I. Gardner