With Means To Increase Active Junction Area (e.g., Grooved Or Convoluted Surface) Patents (Class 257/599)
  • Patent number: 10388743
    Abstract: This invention relates to interdigitated electrodes for power electronic and optoelectronic devices where field and current distribution determine the device performance. Described are geometries based on rounded asymmetrical fingers and electrode bases of varying width. Simulations demonstrate benefits for reducing self-heating and thermal power loss, which reduces overall on-state resistance and increases reverse break down voltages.
    Type: Grant
    Filed: October 13, 2017
    Date of Patent: August 20, 2019
    Inventors: Zhanming Li, Yue Fu, Wai Tung Ng, Yan-Fei Liu
  • Patent number: 8492823
    Abstract: Disclosed is a semiconductor structure, which includes a non-planar varactor having a geometrically designed depletion zone with a taper, as to provide improved Cmax/Cmin with low series resistance. Because of the taper, the narrowest portion of the depletion zone can be designed to be fully depleted, while the remainder of the depletion zone is only partially depleted. The fabrication of semiconductor structure may follow that of standard FinFET process, with a few additional or different steps. These additional or different steps may include formation of a doped trapezoidal (or triangular) shaped silicon mesa, growing/depositing a gate dielectric, forming a gate electrode over a portion of the mesa, and forming a highly doped contact region in the mesa where it is not covered by the gate electrode.
    Type: Grant
    Filed: May 28, 2009
    Date of Patent: July 23, 2013
    Assignee: International Business Machines Corporation
    Inventor: Edward J. Nowak
  • Patent number: 8471363
    Abstract: A semiconductor device includes a substrate, a first single conductor, a single insulator, and a second single conductor. The substrate includes first and second regions located adjacent to each other. The first region has blind holes, each of which has an opening on a front surface of the substrate. The second region has a through hole penetrating the substrate. A width of each blind hole is less than a width of the through hole. The first single conductor is formed on the front surface of the substrate in such a manner that an inner surface of each blind hole and an inner surface of the through hole are covered with the first single conductor. The single insulator is formed on the first single conductor. The second single conductor is formed on the single insulator and electrically insulated form the first single conductor.
    Type: Grant
    Filed: September 27, 2011
    Date of Patent: June 25, 2013
    Assignee: Denso Corporation
    Inventors: Kazushi Asami, Yasuhiro Kitamura
  • Patent number: 8217497
    Abstract: The embodiments of the invention provide a structure, method, etc. for a fin differential MOS varactor diode. More specifically, a differential varactor structure is provided comprising a substrate with an upper surface, a first vertical anode plate, and a second vertical anode plate electrically isolated from the first vertical anode plate. Moreover, a semiconductor fin comprising a cathode is between the first vertical anode plate and the second vertical anode plate, wherein the semiconductor fin, the first vertical anode plate, and the second vertical anode plate are each positioned over the substrate and perpendicular to the upper surface of the substrate.
    Type: Grant
    Filed: January 17, 2007
    Date of Patent: July 10, 2012
    Assignee: International Business Machines Corporation
    Inventors: Bradley A. Orner, Edward J. Nowak, Robert M. Rassel
  • Patent number: 7994563
    Abstract: A device is presented. The device includes a substrate with a first well of a first polarity type. The first well defines a varactor region and comprises a lower first well boundary located above a bottom surface of the substrate. A second well in the varactor region is also included in the device. The second well comprises a buried well of a second polarity type having an upper second well boundary disposed below an upper portion of the first well from an upper first well boundary to the upper second well boundary and a lower second well boundary disposed above the lower first well boundary, wherein an interface of the second well and the upper portion of the first well forms a shallow PN junction in the varactor region. The device also includes a gate structure in the varactor region. The upper portion of the first well beneath the gate structure forms a channel region of the device.
    Type: Grant
    Filed: November 11, 2009
    Date of Patent: August 9, 2011
    Assignee: Global Foudries Singapore PTE. Ltd.
    Inventors: Manju Sarkar, Purakh Raj Verma
  • Patent number: 7989922
    Abstract: An array of deep trenches is formed in a doped portion of the semiconductor substrate, which forms a lower electrode. A dielectric layer is formed on the sidewalls of the array of deep trenches. The array of deep trenches is filled with a doped semiconductor material to form an upper electrode comprising a top plate portion and a plurality of extension portions into the array of trenches. In a depletion mode, the bias condition across the dielectric layer depletes majority carriers within the top electrode, thus providing a low capacitance. In an accumulation mode, the bias condition attracts majority carriers toward the dielectric layer, providing a high capacitance. Thus, the trench metal-oxide-semiconductor (MOS) varactor provides a variable capacitance depending on the polarity of the bias.
    Type: Grant
    Filed: February 8, 2008
    Date of Patent: August 2, 2011
    Assignee: International Business Machines Corporation
    Inventors: Randy W. Mann, Jae-Eun Park, Richard A. Wachnik
  • Patent number: 7989302
    Abstract: Methods of forming hyper-abrupt p-n junctions and design structures for an integrated circuit containing devices structures with hyper-abrupt p-n junctions. The hyper-abrupt p-n junction is defined in a SOI substrate by implanting a portion of a device layer to have one conductivity type and then implanting a portion of this doped region to have an opposite conductivity type. The counterdoping defines the hyper-abrupt p-n junction. A gate structure carried on a top surface of the device layer operates as a hard mask during the ion implantations to assist in defining a lateral boundary for the hyper-abrupt p-n junction.
    Type: Grant
    Filed: June 7, 2010
    Date of Patent: August 2, 2011
    Assignee: International Business Machines Corporation
    Inventors: Jeffrey B. Johnson, Alvin J. Joseph, Robert M. Rassel, Yun Shi
  • Patent number: 7910941
    Abstract: A light-emitting diode (LED) apparatus includes an epitaxial multilayer, a micro/nano rugged layer and an anti-reflection layer. The epitaxial multilayer has a first semiconductor layer, an active layer and a second semiconductor layer in sequence. The micro/nano rugged layer is disposed on the first semiconductor layer of the epitaxial multilayer. The anti-reflection layer is disposed on the micro/nano rugged layer. In addition, a manufacturing method of the LED apparatus is also disclosed.
    Type: Grant
    Filed: March 28, 2008
    Date of Patent: March 22, 2011
    Assignee: Delta Electronics, Inc.
    Inventors: Shih-Peng Chen, Ching-Chuan Shiue, Chao-Min Chen, Horng-Jou Wang, Huang-Kun Chen
  • Patent number: 7804119
    Abstract: Device structures with hyper-abrupt p-n junctions, methods of forming hyper-abrupt p-n junctions, and design structures for an integrated circuit containing devices structures with hyper-abrupt p-n junctions. The hyper-abrupt p-n junction is defined in a SOI substrate by implanting a portion of a device layer to have one conductivity type and then implanting a portion of this doped region to have an opposite conductivity type. The counterdoping defines the hyper-abrupt p-n junction. A gate structure carried on a top surface of the device layer operates as a hard mask during the ion implantations to assist in defining a lateral boundary for the hyper-abrupt-n junction.
    Type: Grant
    Filed: April 8, 2008
    Date of Patent: September 28, 2010
    Assignee: International Business Machines Corporation
    Inventors: Jeffrey B. Johnson, Alvin J. Joseph, Robert M. Rassel, Yun Shi
  • Patent number: 7696604
    Abstract: Methods and heterostructure barrier varactor (HBV) diodes optimized for application with frequency multipliers at providing outputs at submillimeter wave frequencies and above. The HBV diodes include a silicon-containing substrate, an electrode over the silicon-containing substrate, and one or more heterojunction quantum wells of alternating layers of Si and SiGe of one or more electrodes of the diode. Each SiGe quantum well preferably has a floating SiGe layer between adjacent SiGe gradients followed by adjacent Si layers, such that, a single homogeneous structure is provided characterized by having no distinct separations. The plurality of Si/SiGe heterojunction quantum wells may be symmetric or asymmetric.
    Type: Grant
    Filed: October 23, 2007
    Date of Patent: April 13, 2010
    Assignee: International Business Machines Corporation
    Inventors: Erik M. Dahlstrom, Alvin J. Joseph, Robert M. Rassel, David C. Sheridan
  • Publication number: 20090200642
    Abstract: An array of deep trenches is formed in a doped portion of the semiconductor substrate, which forms a lower electrode. A dielectric layer is formed on the sidewalls of the array of deep trenches. The array of deep trenches is filled with a doped semiconductor material to form an upper electrode comprising a top plate portion and a plurality of extension portions into the array of trenches. In a depletion mode, the bias condition across the dielectric layer depletes majority carriers within the top electrode, thus providing a low capacitance. In an accumulation mode, the bias condition attracts majority carriers toward the dielectric layer, providing a high capacitance. Thus, the trench metal-oxide-semiconductor (MOS) varactor provides a variable capacitance depending on the polarity of the bias.
    Type: Application
    Filed: February 8, 2008
    Publication date: August 13, 2009
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Randy W. Mann, Jae-Eun Park, Richard Andre Wachnik
  • Patent number: 7560798
    Abstract: Disclosed is a semiconductor structure, which includes a non-planar varactor having a geometrically designed depletion zone with a taper, as to provide improved Cmax/Cmin with low series resistance. Because of the taper, the narrowest portion of the depletion zone can be designed to be fully depleted, while the remainder of the depletion zone is only partially depleted. The fabrication of semiconductor structure may follow that of standard FinFET process, with a few additional or different steps. These additional or different steps may include formation of a doped trapezoidal (or triangular) shaped silicon mesa, growing/depositing a gate dielectric, forming a gate electrode over a portion of the mesa, and forming a highly doped contact region in the mesa where it is not covered by the gate electrode.
    Type: Grant
    Filed: February 27, 2006
    Date of Patent: July 14, 2009
    Assignee: International Business Machines Corporation
    Inventor: Edward J. Nowak
  • Publication number: 20080164507
    Abstract: An area-efficient gated diode includes a semiconductor layer of a first conductivity type, an active region of a second conductivity type formed in the semiconductor layer proximate an upper surface thereof, and at least one trench electrode extending vertically through the active region and at least partially into the semiconductor layer. A first terminal of the gated diode is connected to the trench electrode, and a second terminal is connected to the active region. The gated diode is operative in one of at least first an second modes as a function of a voltage potential applied between the first and second terminals. The first mode is characterized by the creation of an inversion layer in the semiconductor layer surrounding the trench electrode. The gated diode has a first capacitance in the first mode and a second capacitance in the second mode, the first capacitance being greater than the second capacitance.
    Type: Application
    Filed: March 19, 2008
    Publication date: July 10, 2008
    Applicant: International Business Machines Corporation
    Inventors: Leland Chang, Robert H. Dennard, David M. Fried, Wing Kin Luk
  • Patent number: 7304358
    Abstract: A MOS transistor with a deformable gate formed in a semiconductor substrate, including source and drain areas separated by a channel area extending in a first direction from the source to the drain and in a second direction perpendicular to the first one, a conductive gate beam placed at least above the channel area extending in the second direction between bearing points placed on the substrate on each side of the channel area, and such that the surface of the channel area is hollow and has a shape similar to that of the gate beam when said beam is in maximum deflection towards the channel area.
    Type: Grant
    Filed: September 15, 2005
    Date of Patent: December 4, 2007
    Assignees: STMicroelectronics S.A., Commissariat a l'Energie Atomique
    Inventors: Pascal Ancey, Nicolas Abele, Fabrice Casset
  • Patent number: 7157766
    Abstract: A variable capacitor comprising a substrate having a first type ion-doped buried layer, a first type ion-doped well, a second type ion-doped region and a conductive layer thereon. The first type ion-doped well is formed within the substrate. The first type ion-doped well has a cavity. The first type ion-doped buried layer is in the substrate underneath the first type ion-doped well. The first type ion-doped buried layer and the first type ion-doped well are connected. The second type ion-doped region is at the bottom of the cavity of the first type ion-doped well. The conductive layer is above and in connection with the first type ion-doped buried layer.
    Type: Grant
    Filed: August 18, 2004
    Date of Patent: January 2, 2007
    Assignee: United Microelectronics Corp.
    Inventors: Jing-Horng Gau, Anchor Chen
  • Patent number: 7141864
    Abstract: There is disclosed a semiconductor device comprising at least one capacitive element group having a plurality of unit capacitive elements. At least one lead-out electrode for bottom electrodes of the unit capacitive elements of the capacitive element group is provided along a circumference going around top electrodes as a whole of the capacitive element group. The at least one lead-out electrode is provided so as to surround the top electrodes as a whole of the capacitive element group.
    Type: Grant
    Filed: July 15, 2004
    Date of Patent: November 28, 2006
    Assignee: Sanyo Electric Co, Ltd.
    Inventor: Satoru Kaneko
  • Patent number: 7060610
    Abstract: The present invention relates to a method for forming a contact in a semiconductor device. The method includes the steps of: forming a P-type source/drain junction in a substrate; forming an inter-layer insulation layer on the substrate; forming a contact hole exposing at least one portion of the P-type source/drain junction by etching the inter-layer insulation layer; forming a plug ion implantation region by implanting boron fluoride ions into the exposed portion of the P-type source/drain junction, the boron fluoride ion having the less bonding number of fluorine than 49BF2; performing an activation annealing process for activating dopants implanted into the plug ion implantation region; and forming a contact connected to the P-type source/drain junction through the contact hole.
    Type: Grant
    Filed: April 7, 2004
    Date of Patent: June 13, 2006
    Assignee: Hynix Semiconductor Inc.
    Inventor: Min-Yong Lee
  • Patent number: 6933796
    Abstract: A voltage controlled oscillating circuit operable to output a variable frequency, includes a variable capacitance element with the variable frequency varying with a variation in capacitance of the variable capacitance element. The variable capacitance element is provided by a bipolar transistor. The capacitance of the variable capacitance element is achieved by combining the capacitance by the PN junction between the emitter layer and the base layer and capacitance formed by the PN junction between the base layer and the collector layer in a bipolar transistor, and is controlled by a voltage applied between the emitter layer and the collector layer of the bipolar transistor.
    Type: Grant
    Filed: October 20, 2003
    Date of Patent: August 23, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Satoshi Suzuki, Takayuki Matsuzuka, Kenichiro Choumei
  • Patent number: 6882029
    Abstract: A PN-junction varactor includes a first ion well of first conductivity type formed on a semiconductor substrate of second conductivity type. A first dummy gate is formed over the first ion well. A first gate dielectric layer is formed between the first dummy gate and the first ion well. A second dummy gate is formed over the first ion well at one side of the first dummy gate. A second gate dielectric layer is formed between the second dummy gate and the first ion well. A first heavily doped region of the second conductivity type is located in the first ion well between the first dummy gate and the second dummy gate. The first heavily doped region of the second conductivity type serving as an anode of the PN-junction varactor.
    Type: Grant
    Filed: November 27, 2003
    Date of Patent: April 19, 2005
    Assignee: United Microelectronics Corp.
    Inventors: Jing-Horng Gau, Anchor Chen
  • Patent number: 6855596
    Abstract: A method for manufacturing a trench capacitor includes the step of etching a shallow isolation trench in a two-step process flow. During a first etching step, an etch chemistry based on chlorine or bromine performs a highly selective etch for silicon. During a second step, the etch chemistry is based on SiF4 and O2 which rather equally etches polysilicon and the collar isolation. On top of the wafer, the deposition of silicon oxide on the hard mask predominates and avoids an erosion of the hard mask. On the bottom of the trench the conformal etching of polysilicon and collar isolation predominates. The method provides an economic process flow and is suitable for small feature sizes.
    Type: Grant
    Filed: November 17, 2003
    Date of Patent: February 15, 2005
    Assignee: Infineon Technologies AG
    Inventors: Gabriele Fichtl, Jana Haensel, Thomas Metzdorf, Thomas Morgenstern
  • Patent number: 6835977
    Abstract: A variable capacitor comprising a substrate having a first type ion-doped buried layer, a first type ion-doped well, a second type ion-doped region and a conductive layer thereon. The first type ion-doped well is formed within the substrate. The first type ion-doped well has a cavity. The first type ion-doped buried layer is in the substrate underneath the first type ion-doped well. The first type ion-doped buried layer and the first type ion-doped well are connected. The second type ion-doped region is at the bottom of the cavity of the first type ion-doped well. The conductive layer is above and in connection with the first type ion-doped buried layer.
    Type: Grant
    Filed: March 5, 2002
    Date of Patent: December 28, 2004
    Assignee: United Microelectronics Corp.
    Inventors: Jing-Horng Gan, Anchor Chen
  • Publication number: 20040245604
    Abstract: The present invention provides an varactor, a method of manufacture thereof. In an exemplary embodiment, the varactor includes a semiconductor substrate and well of a first and second conductivity type, respectively. A conductive region in the well has a same conductivity type as the well but a lower resistivity than the well. At least a portion of the well is between at least two sides of the conductive region and an area delineated by an outer perimeter of a conductive layer over the well. Such varactors have a lower series resistance and therefore have an increased quality factor.
    Type: Application
    Filed: June 4, 2003
    Publication date: December 9, 2004
    Applicant: Agere Systems Inc.
    Inventors: Shye Shapira, Debra Johnson, Shahriar Moinian
  • Patent number: 6825089
    Abstract: The present invention provides an varactor, a method of manufacture thereof. In an exemplary embodiment, the varactor includes a semiconductor substrate and well of a first and second conductivity type, respectively. A conductive region in the well has a same conductivity type as the well but a lower resistivity than the well. At least a portion of the well is between at least two sides of the conductive region and an area delineated by an outer perimeter of a conductive layer over the well. Such varactors have a lower series resistance and therefore have an increased quality factor.
    Type: Grant
    Filed: June 4, 2003
    Date of Patent: November 30, 2004
    Assignee: Agere Systems Inc.
    Inventors: Shye Shapira, Debra Johnson, Shahriar Moinian
  • Publication number: 20040173876
    Abstract: Micro-electro-mechanical system (MEMS) variable capacitor apparatuses, system and related methods are provided.
    Type: Application
    Filed: December 15, 2003
    Publication date: September 9, 2004
    Inventors: Francois-Xavier Musalem, Arthur S. Morris, John Richard Gilbert, Siebe Bouwstra, Randy J. Richards
  • Patent number: 6787882
    Abstract: A semiconductor device includes a plurality of barrier layers and a plurality of quantum well layers which are alternately interleaved with each other and disposed on a substrate of semiconductor material so as to form a multiple-heterojunction varactor diode. The barrier layers and quantum well layers are doped with impurities. The varactor diode includes an ohmic contact which is electrically connected to a heavily doped embedded region and a Schottky contact which is electrically connected to a depletion region of the diode. The ohmic contact and the Schottky contact enable an external voltage source to be applied to the contacts so as to provide a bias voltage to the varactor diode. A variable capacitance is produced as a result of the depletion region varying with a variation in the bias voltage. The varactor diode also provides a constant series resistance.
    Type: Grant
    Filed: October 2, 2002
    Date of Patent: September 7, 2004
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Steven Kirchoefer
  • Patent number: 6703681
    Abstract: The invention concerns a variable capacitance capacitor comprising a periodic structure of raised zones (5) separated by recesses (6) formed in a type N semiconductor substrate (1). The walls of the raised zones and the base of the recesses are coated with a conductive layer (9, 10). The substrate is connected to a first terminal (A) of the capacitor and the conductive layer to a second terminal (B) of the capacitor. At least the base of the recesses or the side of the raised zones comprises type P regions (8), the pitch of the raised parts being selected so that the space charging zones linked to the type P regions are joined when the voltage difference between said terminals exceeds a predetermined threshold. The zones not comprising type P regions are coated with an insulant (7) and a highly doped N region (10) is formed beneath the insulant.
    Type: Grant
    Filed: May 16, 2003
    Date of Patent: March 9, 2004
    Assignee: Centre National de la Recherche Scientifique
    Inventors: Jean-Louis Sanchez, Jean-Pierre Laur, Hedi Hakim, Patrick Austin, Jean Jalade, Marie Breil
  • Patent number: 6661069
    Abstract: A three-dimensional micro- electromechanical (MEM) varactor is described wherein a movable beam and fixed electrode are respectively fabricated on separate substrates coupled to each other. The movable beam with comb-drive electrodes are fabricated on the “chip side” while the fixed bottom electrode is fabricated on a separated substrate “carrier side”. Upon fabrication of the device on both surfaces of the substrate, the chip side device is diced and “flipped over”, aligned and joined to the “carrier” substrate to form the final device. Comb-drive (fins) electrodes are used for actuation while the motion of the electrode provides changes in capacitance. Due to the constant driving forces involved, a large capacitance tuning range can be obtained. The three dimensional aspect of the device avails large surface area. When large aspect ratio features are provided, a lower actuation voltage can be used.
    Type: Grant
    Filed: October 22, 2002
    Date of Patent: December 9, 2003
    Assignee: International Business Machines Corporation
    Inventors: Anil K. Chinthakindi, Robert A. Groves, Kenneth J. Stein, Seshadri Subbanna, Richard P. Volant
  • Publication number: 20030173647
    Abstract: An array of nanometric dimensions consisting of two or more arms, positioned side by side, wherein the arms are of such nanometric dimensions that the beams can be moved or deformed towards or away from one another by means of a low voltage applied between the beams, whereby to produce a desired optical, electronic or mechanical effect. At nanometer scale dimensions structures previously treated as rigid become flexible, and this flexibility can be engineered since it is a direct consequence of material and dimensions. Since the electrostatic force between the two arms is inversely proportional to the square of the distance, a very considerable force will be developed with a low voltage of the order of 1-5 volts, which is sufficient to deflect the elements towards or away from one another.
    Type: Application
    Filed: August 12, 2002
    Publication date: September 18, 2003
    Inventors: Lars G. Montelius, Torbjorn G.I. Ling, Andrej Litwin
  • Publication number: 20030085450
    Abstract: The present invention concerns an integrated variable capacitance device comprising at least one membrane (12) forming at least one mobile armature and having at least one principal face facing at least one fixed armature. In accordance with the invention, the membrane has at least one rigidity rib (32) lying in a perpendicular direction to said principal face.
    Type: Application
    Filed: October 15, 2002
    Publication date: May 8, 2003
    Applicant: COMMISSARIAT A L'ENERGIE ATOMIQUE
    Inventor: Gilles Delapierre
  • Patent number: 6489666
    Abstract: A semiconductor device (102) comprises an N type semiconductor substrate (1). A P layer (22) is formed in a first surface (S1) of the semiconductor substrate (1), and a P layer (23) is formed in the semiconductor substrate (1) and in contact with the first surface (S1) and a second surface (S2) of the semiconductor substrate (1) corresponding to a beveled surface. The P layer (23) surrounds the P layer (22) in non-contacting relationship with the P layer (22). A separation distance (D) between the P layers (22, 23) is set at not greater than 50 &mgr;m. A distance (D23) between a third surface (S3) of the semiconductor substrate (1) and a portion of the P layer (23) which is closer to the third surface (S3) is less than a distance (D22) between the third surface (S3) and a portion of the P layer (22) which is closer to the third surface (S3).
    Type: Grant
    Filed: July 25, 2000
    Date of Patent: December 3, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoshihiro Yamaguchi, Katsumi Satoh, Noritoshi Hirano
  • Patent number: 6369671
    Abstract: A semiconductor structure having a substrate, an insulator above a portion of the substrate, a conductor above the insulator; and at least two contact regions in the substrate on opposite sides of the portion of the substrate, wherein a voltage between the contact regions modulates a capacitance of the conductor.
    Type: Grant
    Filed: March 30, 1999
    Date of Patent: April 9, 2002
    Assignee: International Business Machines Corporation
    Inventors: Claude L. Bertin, Anthony R. Bonaccio, Howard L. Kalter, Thomas M. Maffitt, Jack A. Mandelman, Edward J. Nowak, William R. Tonti
  • Patent number: 6316819
    Abstract: A multilayer ZnO polycrystalline diode that protects against electrostatic discharges, over-current, and voltage surges is provided. The polycrystalline diode includes a block having a plurality of polycrystalline layers in parallel having a first lateral side and a second lateral side. A polycrystalline system is formed by a network of the ZnO diodes. Each diode further includes a plurality of inner electrodes, wherein each inner electrode includes metal and is placed among the plurality of parallel polycrystalline layers, and wherein one end of each inner electrode is placed to alternately terminate at one of the first lateral side and the second lateral side of the block, and wherein the remainder of each inner electrode is surrounded by the parallel polycrystalline layers. A pair of outer electrodes, each including metal and covering each of the first lateral side and the second lateral side of the block are also provided.
    Type: Grant
    Filed: November 13, 1998
    Date of Patent: November 13, 2001
    Assignee: Keko-Varicon
    Inventor: Zoran Zivic
  • Patent number: 6018175
    Abstract: In a semiconductor device, a capacitor is provided which has a gap in at least one of its plates. The gap is small enough so that fringe capacitance between the sides of this gap and the opposing plate at least compensates, if not overcompensates, for the missing conductive material that would otherwise fill the gap and add to parallel capacitance. As a result, the capacitance of a storage device can be increased without taking up more die area. Alternatively, the size of a capacitor can be reduced with no decrease in capacitance. Various gap configurations and methods for providing them are also within the scope of the current invention.
    Type: Grant
    Filed: September 3, 1998
    Date of Patent: January 25, 2000
    Assignee: Micron Technology, Inc.
    Inventors: David Y. Kao, James Peacher
  • Patent number: 5747865
    Abstract: An area-variable varactor diode is disclosed, in which the capacitance can be arbitrarily varied under an applied bias voltage. The area-variable varactor diode is characterized in that, in order to ensure freedom to designing the epi-layer, to obtain the desired capacitance characteristics, and to facilitate the integration with other elements, a steeply varied depletion layer area is provided through a variation of the surface layout area, and thus, varied capacitance characteristics are obtained. In steeply varying the area of the depletion layer, an etching of the active layer, a selective epi-layer growth, and an ion implantation are carried out or a combination of them is carried out. The capacitance characteristics are varied in accordance with the pattern of the mask, and therefore, a restriction is not imposed on the epi-layer, with the result that an integration with other elements becomes easy.
    Type: Grant
    Filed: February 18, 1997
    Date of Patent: May 5, 1998
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Dong-Wook Kim, Jeong-Hwan Son, Song-Cheol Hong, Yeong-Se Kwon
  • Patent number: 5663584
    Abstract: (MOS) device systems-utilizing Schottky barrier source and drain to channel region junctions are disclosed. Experimentally derived results which demonstrate operation of fabricated N-channel and P-channel Schottky barrier (MOSFET) devices, and of fabricated single devices with operational characteristics similar to (CMOS) and to a non-latching (SRC) are reported. Use of essentially non-rectifying Schottky barriers in (MOS) structures involving highly doped and the like and intrinsic semiconductor to allow non-rectifying interconnection of, and electrical accessing of device regions is also disclosed. Insulator effected low leakage current device geometries and fabrication procedures therefore are taught.
    Type: Grant
    Filed: December 29, 1994
    Date of Patent: September 2, 1997
    Inventor: James D. Welch