Devices Using Mott Metal-insulator Transition, E.g., Field-effect Transistors (epo) Patents (Class 257/E49.002)
  • Patent number: 8330135
    Abstract: Provided are a germanium (Ge) based metal-insulator transition (MIT) thin film which is formed of a Ge single-element material instead of a compound material of two or more elements and by which material growth may be easily performed and a problem of a second phase characteristic in accordance with a structural defect and an included impurity may be solved, an MIT device including the MIT thin film, and a method of fabricating the MIT device. The MIT device includes a substrate; a germanium (Ge) based MIT thin film which is formed of a Ge single-element material on the substrate and in which a discontinuous MIT occurs at a predetermined transition voltage; and at least two thin film electrodes contacting the Ge based MIT thin film, wherein the discontinuous MIT occurs in the Ge based MIT thin film due to a voltage or a current which is applied through the thin film electrodes.
    Type: Grant
    Filed: June 20, 2008
    Date of Patent: December 11, 2012
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Sung-Youl Choi, Bong-Jun Kim, Yong-Wook Lee, Jae-Yeob Shim, Hyun-Tak Kim
  • Patent number: 8076662
    Abstract: Phase transitions (such as metal-insulator transitions) are induced in oxide structures (such as vanadium oxide thin films) by applying an electric field. The electric field-induced phase transitions are achieved in VO2 structures that scale down to nanometer range. In some embodiments, the optical and/or dielectric properties of the oxide structures are actively tuned by controllably varying the applied electric field. Applying a voltage to a single-phase oxide material spontaneously leads to the formation of insulating and conducting regions within the active oxide material. The dimensions and distributions of such regions can be dynamically tuned by varying the applied electric field and/or the temperature. In this way, oxide materials with dynamically tunable optical and/or dielectric properties are created.
    Type: Grant
    Filed: November 27, 2009
    Date of Patent: December 13, 2011
    Assignee: President and Fellows of Harvard College
    Inventors: Shriram Ramanathan, Changhun Ko
  • Patent number: 7994573
    Abstract: A field effect transistor (FET) includes body regions of a first conductivity type over a semiconductor region of a second conductivity type. The body regions form p-n junctions with the semiconductor region. Source regions of the second conductivity type extend over the body regions. The source regions form p-n junctions with the body regions. Gate electrodes extend adjacent to but are insulated from the body regions by a gate dielectric. A carbon-containing region extends in the semiconductor region below the body regions.
    Type: Grant
    Filed: December 12, 2008
    Date of Patent: August 9, 2011
    Assignee: Fairchild Semiconductor Corporation
    Inventor: James Pan
  • Patent number: 7964866
    Abstract: Embodiments of the invention relate to apparatus, system and method for use of a memory cell having improved power consumption characteristics, using a low-bandgap material quantum well structure together with a floating body cell.
    Type: Grant
    Filed: May 12, 2008
    Date of Patent: June 21, 2011
    Assignee: Intel Corporation
    Inventors: Titash Rakshit, Gilbert Dewey, Ravi Pillarisetty
  • Patent number: 7929308
    Abstract: A power device package controls heat generation of a power device using a semi-permanent metal-insulator transition (MIT) device instead of a fuse, and emits heat generated by the power device through a small-sized heat sink provided only in one region on the power device, thereby ensuring excellent dissipation of heat. Therefore, the power device package can be usefully applied to any electric/electronic circuit that uses a power device.
    Type: Grant
    Filed: August 5, 2009
    Date of Patent: April 19, 2011
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Sang Kuk Choi, Hyun Tak Kim, Byung Gyu Chae, Bong Jun Kim
  • Publication number: 20100301300
    Abstract: Provided are a 3-terminal MIT switch which can easily control a discontinuous MIT jump and does not need a conventipnal gate insulating layer, a switching system including the 3-terminal MIT switch, and a method of controlling an MIT of the 3-terminal MIT switch. The 3-terminal MIT switch includes a 2-terminal MIT device, which generates discontinuous MIT in a transition voltage, an inlet electrode (200) and an outlet electrode (300), which are respectively connected to each terminal of the 2-terminal MIT device, and a control electrode (400), which is connected to the inlet electrode and includes an external terminal separated from an external terminal of the inlet electrode, wherein an MIT of the 2-terminal MIT device is controlled according to a voltage or a current applied to the control electrode. The switching system includes the 3-terminal MIT switch, a voltage source connected to the inlet electrode, and a control source connected to the control electrode.
    Type: Application
    Filed: May 7, 2008
    Publication date: December 2, 2010
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Hyun-Tak Kim, Yong-Wook Lee, Bong-Jun Kim, Sung-Youl Choi, Sun-Jin Yun
  • Patent number: 7812346
    Abstract: A fabrication method is used in conjunction with a semiconductor device having a metal oxide active layer less than 100 nm thick and the upper major surface and the lower major surface have material in abutting engagement to form underlying interfaces and overlying interfaces. The method of fabrication includes controlling interfacial interactions in the underlying interfaces and the overlying interfaces to adjust the carrier density in the adjacent metal oxide by selecting a metal oxide for the metal oxide active layer and by selecting a specific material for the material in abutting engagement. The method also includes one or both steps of controlling interactions in underlying interfaces by surface treatment of an underlying material forming a component of the underlying interface and controlling interactions in overlying interfaces by surface treatment of the metal oxide film performed prior to deposition of material on the metal oxide layer.
    Type: Grant
    Filed: July 16, 2008
    Date of Patent: October 12, 2010
    Assignee: Cbrite, Inc.
    Inventors: Chan-Long Shieh, Gang Yu
  • Patent number: 7728327
    Abstract: Provided is a 2-terminal semiconductor device that uses an abrupt MIT semiconductor material layer. The 2-terminal semiconductor device includes a first electrode layer, an abrupt MIT semiconductor organic or inorganic material layer having an energy gap less than 2eV and holes in a hole level disposed on the first electrode layer, and a second electrode layer disposed on the abrupt MIT semiconductor organic or inorganic material layer. An abrupt MIT is generated in the abrupt MIT semiconductor material layer by a field applied between the first electrode layer and the second electrode layer.
    Type: Grant
    Filed: December 13, 2004
    Date of Patent: June 1, 2010
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Hyun Tak Kim, Doo Hyeb Youn, Byung Gyu Chae, Kwang Yong Kang, Yong Sik Lim, Gyungock Kim, Sunglyul Maeng, Seong Hyun Kim
  • Publication number: 20090321709
    Abstract: A memory element comprises a first electrode, a second electrode, and a resistance variable film 2 which is disposed between the first and second electrodes to be connected to the first and second electrodes, a resistance value of the resistance variable film 2 varying based on voltage applied between the first and second electrodes, the resistance variable film 2 includes a layer 2a made of Fe3O4 and a layer 2b made of Fe2O3 or a spinel structure oxide which is expressed as MFe2O4 (M: metal element except for Fe); and the layer 2a made of Fe3O4 is thicker than the layer 2b made of Fe2O3 or the spinel structure oxide.
    Type: Application
    Filed: August 17, 2007
    Publication date: December 31, 2009
    Inventors: Shunsaku Muraoka, Satoru Fujii, Satoru Mitani, Koichi Osano
  • Publication number: 20090200581
    Abstract: A double-gate semiconductor device provides a high breakdown voltage allowing for a large excursion of the output voltage that is useful for power applications. The double-gate semiconductor device may be considered a double-gate device including a MOS gate and a junction gate, in which the bias of the junction gate may be a function of the gate voltage of the MOS gate. The breakdown voltage of the double-gate semiconductor device is the sum of the breakdown voltages of the MOS gate and the junction gate. Because an individual junction gate has an intrinsically high breakdown voltage, the breakdown voltage of the double-gate semiconductor device is greater than the breakdown voltage of an individual MOS gate. The double-gate semiconductor device provides improved RF capability in addition to operability at higher power levels as compared to conventional transistor devices.
    Type: Application
    Filed: February 13, 2008
    Publication date: August 13, 2009
    Inventors: Denis A. Masliah, Alexandre G. Bracale, Francis C. Huin, Patrice J. Barroul
  • Publication number: 20090114967
    Abstract: According to some embodiments of the invention, transistors have channel regions between channel-portion holes. Methods of forming the same include at least two channel-portion holes disposed in a semiconductor substrate. Line patterns are formed in parallel to be spaced apart from each other on a main surface of the semiconductor substrate to fill the channel-portion holes. A channel region is disposed in the semiconductor substrate below the line patterns. At this time, the channel region is formed between the channel-portion holes and also covers lower portions of the channel-portion holes. Driving current capability and refresh characteristics of DRAMs utilizing the inventive transistors are improved.
    Type: Application
    Filed: December 29, 2008
    Publication date: May 7, 2009
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Jin-Woo Lee, Tae-Young Chung, Yong-Sung Kim
  • Publication number: 20080258243
    Abstract: A field effect transistor includes: a first nitride semiconductor layer having a plane perpendicular to a (0001) plane or a plane tilted with respect to the (0001) plane as a main surface; a second nitride semiconductor layer formed on the first nitride semiconductor layer and having a wider bandgap than the first nitride semiconductor layer; a third nitride semiconductor layer formed on the second nitride semiconductor layer; and a source electrode and a drain electrode formed so as to contact at least a part of the second nitride semiconductor layer or the third nitride semiconductor layer. A recess that exposes a part of the second nitride semiconductor layer is formed between the source electrode and the drain electrode in the third nitride semiconductor layer. A gate electrode is formed in the recess and an insulating film is formed between the third nitride semiconductor layer and the gate electrode.
    Type: Application
    Filed: April 1, 2008
    Publication date: October 23, 2008
    Inventors: Masayuki Kuroda, Tetsuzo Ueda
  • Patent number: 7439566
    Abstract: A semiconductor memory device may have a lower leakage current and/or higher reliability, e.g., a longer retention time and/or a shorter refresh time. The device may include a switching device and a capacitor. A source of the switching device may be connected to a first end of a metal-insulator transition film resistor, and at least one electrode of the capacitor may be connected to a second end of the metal-insulator transition film resistor. The metal-insulator transition film resistor may transition between an insulator and a conductor according to a voltage supplied to the first and second ends thereof.
    Type: Grant
    Filed: July 13, 2006
    Date of Patent: October 21, 2008
    Assignee: Samsung Electronics, Co., Ltd.
    Inventors: Jae-Woong Hyun, In-Kyeong Yoo, Yoon-Dong Park, Choong-Rae Cho, Sung-Il Cho
  • Publication number: 20080237639
    Abstract: The objective of the present invention is to provide a semiconductor device of a hetero-junction field effect transistor that is capable of obtaining a high output and a high breakdown voltage and a manufacturing method of the same. The present invention is a semiconductor device of a hetero-junction field effect transistor provided with an AlxGa1-xN channel layer with a composition ratio of Al being x (0<x<1) formed on a substrate, an AlyGa1-yN barrier layer with a composition of Al being y (0<y?1) formed on the channel layer, and source/drain electrodes and a gate electrode formed on the barrier layer, wherein the composition ratio y is larger than the composition ratio x.
    Type: Application
    Filed: March 25, 2008
    Publication date: October 2, 2008
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Takuma NANJO, Muneyoshi Suita, Yuji Abe, Toshiyuki Oishi, Yasunori Tokuda
  • Publication number: 20080217682
    Abstract: A device and method for selective placement of charge into a gate stack includes forming gate stacks including a gate dielectric adjacent to a transistor channel and a gate conductor and forming doped regions for transistor operation. A layer rich in a passivating element is deposited over the doped regions and the gate stack, and the layer rich the passivating element is removed from selected transistors. The layer rich in the passivating element is than annealed to drive-in the passivating element to increase a concentration of charge at or near transistor channels on transistors where the layer rich in the passivating element is present. The layer rich in the passivating element is removed.
    Type: Application
    Filed: May 16, 2008
    Publication date: September 11, 2008
    Inventors: John Michael Hergenrother, Zhibin Ren, Dinkar Virendra Singh, Jeffrey William Sleight
  • Publication number: 20080211012
    Abstract: An accumulation-mode field effect transistor includes a drift region of a first conductivity type, channel regions of the first conductivity type over and in contact with the drift region, and gate trenches having sidewalls abutting the channel regions. The gate trenches extend into and terminate within the drift region. The transistor further includes a first plurality of silicon regions of a second conductivity type forming P-N junctions with the channel regions along vertical walls of the first plurality of silicon regions. The first plurality of silicon regions extend into the drift region and form P-N junctions with the drift region along bottoms of the first plurality of silicon regions.
    Type: Application
    Filed: May 2, 2008
    Publication date: September 4, 2008
    Inventors: Christopher Boguslaw Kocon, Praveen Muraleedharan Shenoy