Variable Capacitance Diode (e.g., Varactors) (epo) Patents (Class 257/E29.344)
  • Publication number: 20080246119
    Abstract: Large tuning range junction varactor includes first and second junction capacitors coupled in parallel between first and second varactor terminals. First and second plates of the capacitors are formed by three alternating doped regions in a substrate. The first and third doped regions are of the same type sandwiching the second doped region of the second type. A first input terminal is coupled to the first and third doped regions and a second terminal is coupled to the second doped region. At the interfaces of the doped regions are first and second depletion regions whose width can be varied by varying the voltage across the terminals from zero to full reverse bias.
    Type: Application
    Filed: April 5, 2007
    Publication date: October 9, 2008
    Applicant: Chartered Semiconductor Manufacturing, Ltd.
    Inventors: Manju SARKAR, Purakh Raj Verma
  • Publication number: 20080237676
    Abstract: Disclosed is a varactor and/or variable capacitor. The varactor/variable capacitor includes a plurality of first conductive-type wells vertically formed on a substrate, a plurality of second conductive-type ion implantation areas formed in the first conductive-type wells, at least one second conductive-type plug electrically connected to the second conductive-type ion implantation areas, an isolation layer formed at sides of an uppermost second conductive-type ion implantation area, and a first conductive-type ion implantation area in an uppermost first conductive-type well electrically disconnected from the uppermost second conductive-type ion implantation area by the isolation area.
    Type: Application
    Filed: December 13, 2007
    Publication date: October 2, 2008
    Inventor: Su Lim
  • Publication number: 20080237677
    Abstract: The semiconductor variable capacitor includes a capacitor including an n-well 16 formed in a first region of a semiconductor substrate 10, an insulating film 18 formed over the semiconductor substrate 10 and a gate electrode 20n formed above the n-well 16 with the insulating film 18 interposed therebetween; and a p-well 14 of a second conduction type formed in a second region adjacent to the first region of the semiconductor substrate 10. The gate electrode 20n has an end which is extended to the second region and formed above the p-well 14 with the insulating film 18 interposed therebetween.
    Type: Application
    Filed: March 26, 2008
    Publication date: October 2, 2008
    Applicant: FUJITSU LIMITED
    Inventor: Toshiro FUTATSUGI
  • Publication number: 20080203537
    Abstract: Structure and methods for a differential junction varactor. The structure includes: a silicon first region formed in a silicon substrate, the first region of a first dopant type; and a plurality of silicon second regions in physical and electrical contact with the first region, the plurality of second regions spaced apart and not in physical contact with each other, the plurality of second regions of a second dopant type, the first dopant type different from the second dopant type; a cathode terminal electrically connected to the first region; a first anode terminal electrically connected to a first set of second regions of the plurality of second regions; and a second anode terminal electrically connected to a second set of second silicon regions of the plurality of second regions, second regions of the first set of second regions alternating with second regions of the second set of second regions.
    Type: Application
    Filed: February 28, 2007
    Publication date: August 28, 2008
    Inventors: Frederick Gustav Anderson, Robert Mark Rassel, Nicholas Theodore Schmidt, Xudong Wang
  • Publication number: 20080191260
    Abstract: The semiconductor device comprises a first and a second varactor which are connected in an anti-series configuration. This connection is done such that a first, substantially electrically conductive region is present between a second region with dopant of a first conductivity type and a third region with dopant of the first conductivity type. The second and third regions comprise dopant that is distributed uniformly within the region. The first region is provided with or connected to a contact which has an AC resistance of at least 1 k?.
    Type: Application
    Filed: September 26, 2005
    Publication date: August 14, 2008
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventors: Leonardus Cornelis Nicolaas De Vreede, Lis Karen Nanver, Koen Buisman
  • Publication number: 20080185625
    Abstract: A two-terminal capacitive circuit element 100 includes a MOS transistor including a source 126 and drain 127 separated by a body region 131, and a gate 105 separated from the body 129 by a gate insulator layer 110, and a bypass capacitor 125. The gate node (port2; 115) is AC grounded through the bypass capacitor 125 and the source 126 and drain 127 are tied together (port-1; 120). By toggling the transistor on and off using an appropriate gate to body voltage, the capacitance of the capacitive circuit element 100 between port-1 and port-2 significantly changes.
    Type: Application
    Filed: September 12, 2005
    Publication date: August 7, 2008
    Applicant: UNIVERSITY OF FLORIDA RESEARCH FOUNDATION, INC.
    Inventors: Seong-Mo Yim, Kenneth Kyongyup O
  • Publication number: 20080169495
    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: Application
    Filed: January 17, 2007
    Publication date: July 17, 2008
    Inventors: Bradley A. Orner, Edward J. Nowak, Robert M. Rassel
  • 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
  • Publication number: 20080157159
    Abstract: A metal-on-semiconductor varactor with a high value of Cmax/Cmin comprises a semiconductor bottom plate with an array of semiconductor pillars. The pillars may be in an accumulation mode to provide a high capacitance or in a depletion mode to provide a low capacitance. The maximum capacitance in an accumulation mode is primarily determined by the capacitance of the semiconductor pillars. The minimum capacitance in a depletion mode is primarily determined by a capacitor formed on an inter-pillar semiconductor surface between the semiconductor pillars. The minimum capacitance, and hence the value of Cmax/Cmin may be tuned by adjusting process parameters, design parameters and by alterations in the MOS varactor structure such as forming a highly doped semiconductor layer beneath the inter-pillar semiconductor surface or forming a plate insulator.
    Type: Application
    Filed: December 28, 2006
    Publication date: July 3, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Terence B. Hook, Jae-Eun Park
  • Patent number: 7388276
    Abstract: A varactor is configured with first and second conducting layers, spaced apart from one another such that a given voltage can be applied across the first and second conducting layers. Further, an insulator arrangement includes at least one insulator layer disposed between the first and second conducting layers, configured to cooperate with the first and second conducting layers to produce a charge pool which changes responsive to changes in the given voltage such that a device capacitance value between the first and second conducting layers changes responsive to the given voltage. The insulator arrangement can include one layer, two distinct layers or more than two distinct layers. One or more of the layers can be an amorphous material. A zero-bias voltage version of the varactor is also described.
    Type: Grant
    Filed: July 7, 2005
    Date of Patent: June 17, 2008
    Assignee: The Regents of the University of Colorado
    Inventor: Michael J. Estes
  • Patent number: 7388247
    Abstract: A high precision microelectromechanical capacitor with programmable voltage source includes a monolithic MEMS device having a capacitance actuator, a trim capacitor, and a high precision, programmable voltage source. The trim capacitor has a variable capacitance value, preferably for making fine adjustments in capacitance. The capacitance actuator is preferably mechanically coupled to and electrically isolated from the trim capacitor and is used to control the capacitance value of the trim capacitor. The capacitance adjustment of the trim capacitor is non-destructive and may be repeated indefinitely. The trim capacitor may be adjusted by mechanically changing the distance between its electrodes. The programmable voltage source provides a highly accurate and stable output voltage potential corresponding to control signals for controlling the capacitance actuator.
    Type: Grant
    Filed: May 28, 2003
    Date of Patent: June 17, 2008
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Isaac Lagnado, Paul R. de la Houssaye
  • Publication number: 20080122036
    Abstract: This invention discloses a decoupling capacitor in an integrated circuit, comprising a plurality of dedicated PN diodes with a total junction area greater than one tenth of a total active area of functional devices for which the dedicated PN diodes are intended to protect, a N-type region of the dedicated PN diodes coupling to a positive supply voltage (Vdd), and a P-type region of the dedicated PN diodes coupling to a complimentary lower supply voltage (Vss), wherein the dedicated PN diodes are reversely biased.
    Type: Application
    Filed: August 10, 2006
    Publication date: May 29, 2008
    Inventors: Hsien-Te Chen, Jen-Hang Yang, Chun-Hui Tai
  • Patent number: 7378327
    Abstract: A junction varactor includes a gate finger lying across an ion well of a semiconductor substrate; a gate dielectric situated between the gate finger and the ion well; a first ion diffusion region with first conductivity type located in the ion well at one side of the gate finger, the first ion diffusion region serving as an anode of the junction varactor; and a second ion diffusion region with a second conductivity type located in the ion well at the other side of the gate finger, the second ion diffusion region serving as a cathode of the junction varactor. In operation, the gate of the junction varactor is biased to a gate voltage VG that is not equal to 0 volt.
    Type: Grant
    Filed: June 10, 2007
    Date of Patent: May 27, 2008
    Assignee: United Microelectronics Corp.
    Inventor: Ching-Hung Kao
  • Publication number: 20080111176
    Abstract: Disclosed are embodiments of a transistor that operates as a capacitor and an associated method of tuning capacitance within such a capacitor. The embodiments of the capacitor comprise a field effect transistor with front and back gates above and below a semiconductor layer, respectively. The capacitance value exhibited by the capacitor can be selectively varied between two different values by changing the voltage condition in a source/drain region of the transistor, e.g., using a switch or resistor between the source/drain region and a voltage supply. Alternatively, the capacitance value exhibited by the capacitor can be selectively varied between multiple different values by changing voltage conditions in one or more of multiple channel regions that are flanked by multiple source/drain regions within the transistor. The capacitor will exhibit different capacitance values depending upon the conductivity in each of the channel regions.
    Type: Application
    Filed: November 15, 2006
    Publication date: May 15, 2008
    Inventors: Corey K. Barrows, Joseph A. Iadanza, Edward J. Nowak, Douglas W. Stout, Mark S. Styduhar
  • Publication number: 20080099881
    Abstract: A semiconductor element for macro and micro frequency tuning, and an antenna and a frequency tuning circuit having the semiconductor element, are provided. The semiconductor element includes first and second semiconductors which have a same polarity, a third semiconductor which has a polarity opposite to the polarity of the first and second semiconductors and is interposed between the first and the second semiconductors, a first intrinsic semiconductor which is interposed between the first and the third semiconductors, and a second intrinsic semiconductor which is interposed between the third and the second semiconductors.
    Type: Application
    Filed: March 28, 2007
    Publication date: May 1, 2008
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Chang-won Jung, Jung-han Choi, In-sang Song, Young-eil Kim
  • Publication number: 20080087978
    Abstract: A structure and method comprises a deep sub-collector located in a first epitaxial layer and a doped region located in a second epitaxial layer, which is above the first epitaxial layer. The device further comprises a reach-through structure penetrating from a surface of the device through the first and second epitaxial layers to the deep sub-collector, and a trench isolation structure penetrating from a surface of the device and surrounding the doped region.
    Type: Application
    Filed: October 11, 2006
    Publication date: April 17, 2008
    Inventors: Douglas D. Coolbaugh, Xuefeng Liu, Robert M. Rassel, David C. Sheridan, Steven H. Voldman
  • Publication number: 20080048236
    Abstract: Provided is a parallel-varactor capacitor. The capacitor comprises a first varactor and a second varactor. The first varactor has a first capacitance which varies depending on voltages applied to a first anode and a first cathode. The second varactor has a second capacitance which varies depending on voltages applied to a second anode and a second cathode. The first anode is connected to the second cathode and the first cathode is connected to the second anode.
    Type: Application
    Filed: July 19, 2007
    Publication date: February 28, 2008
    Inventor: Seyeob Kim
  • Patent number: 7335956
    Abstract: A capacitor device selectively combines MOM, MIM and varactor regions in the same layout area of an IC. Two or more types of capacitor regions arranged vertically on a substrate to form the capacitor device. This increase the capacitance per unit of the capacitor device, without occupying an extra layout area.
    Type: Grant
    Filed: February 11, 2005
    Date of Patent: February 26, 2008
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Yueh-You Chen, Chung-Long Chang, Chih-Ping Chao, Chun-Hong Chen
  • Publication number: 20080012091
    Abstract: An LC tack structure. The structure, including a set of wiring levels on top of a semiconductor substrate, the wiring levels stacked on top of each other from a lowest wiring level nearest the substrate to a highest wiring level furthest from the substrate; an inductor in the highest wiring level, the inductor confined within a perimeter of a region of the highest wiring level; and a varactor formed in the substrate, the varactor aligned completely under the perimeter of the region of the highest wiring level. The structure may additionally include an electric shield in a wiring level of the set of wiring levels between the lowest wiring level and the highest wiring level. Alternatively, the inductor includes a magnetic core and alternating electrically non-magnetic conductive metal coils and magnetic coils around the core.
    Type: Application
    Filed: September 24, 2007
    Publication date: January 17, 2008
    Inventors: Hanyi Ding, Kai Feng, Zhong-Xiang He, Xuefeng Liu
  • Patent number: 7259418
    Abstract: A semiconductor device comprises varactor regions Va and transistor regions Tr. An active region for a varactor is formed with a substrate contact impurity diffusion region obtained by doping an N well region with N-type impurity at a relatively high concentration. However, any extension region (or LDD region) as in a varactor of a known semiconductor device is not formed in the active region for a varactor. On the other hand, parts of a P well region located to both sides of the polysilicon gate electrode in the transistor region Tr are formed with high-concentration source/drain regions and extension regions. Therefore, the extendable range of a depletion layer is kept wide to extend the capacitance variable range of the varactor.
    Type: Grant
    Filed: July 23, 2004
    Date of Patent: August 21, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tadashi Kadowaki, Hiroyuki Umimoto, Takato Handa
  • Patent number: 7235862
    Abstract: A semiconductor junction varactor utilizes gate enhancement for enabling the varactor to achieve a high ratio of maximum capacitance to minimum capacitance.
    Type: Grant
    Filed: July 10, 2001
    Date of Patent: June 26, 2007
    Assignee: National Semiconductor Corporation
    Inventor: Constantin Bulucea
  • Publication number: 20070132065
    Abstract: Provided are a paraelectric thin film structure and a high frequency tunable device with the paraelectric thin film structure. The paraelectric thin film structure has a large dielectric constant tuning rate and a low dielectric loss at a high frequency. The paraelectric thin film structure includes a perovskite ABO3 type paraelectric film formed on an oxide single crystal substrate. The paraelectric film is formed of a material selected from Ba(Zrx,Ti1-x)O3, Ba(Hfy,Ti1-y)O3, or Ba(Snz,Ti1-z)O3. Instead of the paraelectric film, the paraelectric thin film structure may include a compositionally graded paraelectric film having at least two paraelectric films formed of the selected material by varying the composition ratio x, y, or z. A high-frequency/phase tunable device employing the paraelectric thin film structure can have improved microwave characteristics and high-speed, low-power-consuming, low-cost characteristics.
    Type: Application
    Filed: March 27, 2006
    Publication date: June 14, 2007
    Inventors: Su Jae Lee, Han Ryu, Seung Moon, Young Kim, Min Kwak, Kwang Kang
  • Publication number: 20070126083
    Abstract: The semiconductor device provided assures stable communication processes. For example, a varactor diode for adjusting the reference frequency is comprised within a digital crystal-controlled oscillating circuit provided as an internal circuit of the front-end circuit for generating the reference oscillation signal of a PLL circuit or the like. The varactor diode is formed to a semiconductor layer DF of the so-called SOI structure in the structure where an embedded insulating layer, a n?type semiconductor region, a p type semiconductor region, and a n+ type semiconductor region are formed in this sequence and the n+ type semiconductor region is connected to a cathode node which becomes the frequency adjusting node. Moreover, a p+ type semiconductor region connected to the p type semiconductor region is formed in both sides of the n+ type semiconductor region, and this p+ type semiconductor region is connected to an anode node to which the ground voltage is applied.
    Type: Application
    Filed: December 5, 2006
    Publication date: June 7, 2007
    Inventors: Kentaro SUZUKI, Ikuya Ono, Tadatoshi Danno
  • Publication number: 20070069264
    Abstract: A ferroelectric varactor suitable for capacitive shunt switching is disclosed. High resistivity silicon with a SiO2 layer and a patterned metallic layer deposited on top is used as the substrate. A ferroelectric thin-film layer deposited on the substrate is used for the implementation of the varactor. A top metal electrode is deposited on the ferroelectric thin-film layer forming a CPW transmission line. By using the capacitance formed by the large area ground conductors in the top metal electrode and bottom metallic layer, a series connection of the ferroelectric varactor with the large capacitor defined by the ground conductors is created. The large capacitor acts as a short to ground, eliminating the need for vias. In one embodiment, the varactor shunt switch can be used as passive sensor with the capability of being wireless.
    Type: Application
    Filed: October 5, 2006
    Publication date: March 29, 2007
    Inventors: Guru Subramanyam, Andre Vorobiev, Spartak Gevorgian
  • Publication number: 20070029587
    Abstract: A MOS varactor is formed having a gate electrode comprising at least two abutting oppositely doped regions shorted together, in which the two regions are implanted simultaneously with source/drain implants for first and second types of transistor; at least one contact to a lower electrode is also formed simultaneously with the source/drain implants for the first type of transistor; the varactor insulator is formed simultaneously with the gate insulator for one type of transistor; and the lower electrode is formed simultaneously with a well for the first type of transistor, so that no additional mask is required.
    Type: Application
    Filed: August 8, 2005
    Publication date: February 8, 2007
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Heidi Greer, Seong-Dong Kim, Robert Rassel, Kunal Vaed
  • Publication number: 20060289942
    Abstract: A memory cell in a semiconductor memory device comprises a variable resistor element configured so that a variable resistor body is sandwiched between a first electrode and a second electrode, and a transistor element capable of controlling a flow of current in the variable resistor element, wherein the transistor element and the variable resistor element are placed one over the other along a direction in which the first electrode, the variable resistor body, and the second electrode of the variable resistor element are layered, and one of the first electrode and the second electrode of the variable resistor element is connected to one electrode of the transistor element.
    Type: Application
    Filed: June 26, 2006
    Publication date: December 28, 2006
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Shinji Horii, Takashi Yokoyama, Tetsuya Ohnishi
  • Publication number: 20060267150
    Abstract: A varactor is configured with first and second conducting layers, spaced apart from one another such that a given voltage can be applied across the first and second conducting layers. Further, an insulator arrangement includes at least one insulator layer disposed between the first and second conducting layers, configured to cooperate with the first and second conducting layers to produce a charge pool which changes responsive to changes in the given voltage such that a device capacitance value between the first and second conducting layers changes responsive to the given voltage. The insulator arrangement can include one layer, two distinct layers or more than two distinct layers. One or more of the layers can be an amorphous material. A zero-bias voltage version of the varactor is also described.
    Type: Application
    Filed: July 7, 2005
    Publication date: November 30, 2006
    Inventor: Michael Estes