Patents by Inventor Rajiv Joshi

Rajiv Joshi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20060203581
    Abstract: An efficient method and computer program for modeling and improving stating memory performance across process variations and environmental conditions provides a mechanism for raising the performance of memory arrays beyond present levels/yields. Statistical (Monte-Carlo) analyses of subsets of circuit parameters are performed for each of several memory performance variables and then sensitivities of each performance variable to 15 each of the circuit parameters are determined. The memory cell design parameters and/or operating conditions of the memory cells are then adjusted in conformity with the sensitivities, resulting in improved memory yield and/or performance. Once a performance level is attained, the sensitivities can then be used to alter the probability distributions of the performance variables to achieve a higher yield.
    Type: Application
    Filed: March 10, 2005
    Publication date: September 14, 2006
    Inventors: Rajiv Joshi, Anirudh Devgan
  • Publication number: 20060192612
    Abstract: A capacitor circuit having improved reliability includes at least first and second capacitors, a first terminal of the first capacitor connecting to a first source providing a first voltage, a first terminal of the second capacitor connecting to a second source providing a second voltage, the first voltage being greater than the second voltage. The capacitor further includes a voltage comparator having a first input for receiving a voltage representative of the first voltage, a second input for receiving a third voltage provided by a third source, and an output for generating a control signal. The control signal is a function of a difference between the voltage representative of the first voltage and the third voltage. A switch is connected to second terminals of the first and second capacitors.
    Type: Application
    Filed: February 25, 2005
    Publication date: August 31, 2006
    Applicant: International Business Machines Corporation
    Inventors: Louis Hsu, Rajiv Joshi, Jack Mandelman
  • Publication number: 20060189110
    Abstract: A semiconductor structure having a body capacitance plate, which is formed with a process that assures that the body capacitance plate is self-aligned to both the source line (SL) diffusion and the bitline diffusion is provided. Thus the amount of overlap between the SL and the bitline diffusions and the body capacitance plate is precisely controlled. More specifically, the present invention forms the structure of a 1T-capacitorless SOI body charge storage cell having sidewall capacitor plates using a process that assures that there is 1) minimal overlap between plate and source/drain diffusions, and 2) that the minimal overlap obtained in the present invention is precisely controlled and is not subject to alignment tolerances. The inventive cell results in larger signal margin, improved performance, smaller chip size, and reduced dynamic power dissipation relative to the prior art.
    Type: Application
    Filed: February 24, 2005
    Publication date: August 24, 2006
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Jack Mandelman, Louis Hsu, Rajiv Joshi
  • Publication number: 20060176732
    Abstract: A CMOS static random access memory (SRAM) and a bit select for the SRAM. The bit select includes a dual single-ended sense receiving a difference signal on a bit line pair and selectively sensing signals developing on each bit line independently of the other. Single ended outputs from the dual-ended sense are provided to an output driver. The output driver provides a pair of selectively-complementary output signals.
    Type: Application
    Filed: February 10, 2005
    Publication date: August 10, 2006
    Inventors: Yuen Chan, Timothy Charest, Rajiv Joshi, Antonio Pelella
  • Publication number: 20060176095
    Abstract: An output L1/L2 staging latch has dual rail inputs that up date the state of the L1 latch whenever the inputs are valid. Static outputs of the L1 latch are latched into the L2 by the L2 clock signal. The L2 latch has a static output that is available immediately, and a dual rail dynamic output whose timing is controlled by a clock signal.
    Type: Application
    Filed: February 9, 2005
    Publication date: August 10, 2006
    Applicant: International Business Machines Corporation
    Inventors: Yuen Chan, Timothy Charest, Rajiv Joshi
  • Publication number: 20060157788
    Abstract: The present invention generally concerns fabrication methods and device architectures for use in memory circuits, and more particularly concerns hybrid silicon-on-insulator (SOI) and bulk architectures for use in memory circuits. Once aspect of the invention concerns CMOS SRAM cell architectures where at least one pair of adjacent NFETs in an SRAM cell have body regions linked by a leakage path diffusion region positioned beneath shallow source/drain diffusions, where the leakage path diffusion region extends from the bottom of the source/drain diffusion to the buried oxide layer, and at least one pair of NFETs from adjacent SRAM cells which have body regions linked by a similar leakage path diffusion region beneath adjacent source/drain diffusions.
    Type: Application
    Filed: January 19, 2005
    Publication date: July 20, 2006
    Applicant: International Business Machines Corporation
    Inventors: Rajiv Joshi, Richard Wachnik, Yue Tan, Kerry Bernstein
  • Publication number: 20060146621
    Abstract: A test circuit and programmable voltage divider that may be used in the test circuit. The programmable voltage divider develops a voltage difference signal that may be digitally selected. The test circuit may be used to test and characterize sense amplifiers. The programmable voltage divider develops a signal with a selected polarity and magnitude that is provided to a sense amplifier being tested. The sense amplifier is set and its output latched. The latch contents are checked against an expected value. The difference voltage may be changed and the path retested to find passing and failing points.
    Type: Application
    Filed: January 3, 2005
    Publication date: July 6, 2006
    Inventors: Yuen Chan, Rajiv Joshi
  • Publication number: 20060109733
    Abstract: A multi-port register file, integrated circuit (IC) chip including one or more multi-port register files and method of reading data from the multi-port register file. The supply to storage latches in multi-port register file is selectively bootstrapped above the supply voltage during accesses.
    Type: Application
    Filed: November 22, 2004
    Publication date: May 25, 2006
    Inventors: Rajiv Joshi, Azeez Bhavnagarwala
  • Publication number: 20060098499
    Abstract: A random access memory includes a memory cell having an access device. The access device is switched on or off in accordance with a signal on a wordline to conduct a memory operation through the access device. A logic circuit is coupled to the wordline to delay or gate the wordline signal until an enable signal has arrived at the logic circuit. The access device improves stability and eliminates early read problems.
    Type: Application
    Filed: November 10, 2004
    Publication date: May 11, 2006
    Inventor: Rajiv Joshi
  • Publication number: 20060059376
    Abstract: A low power consumption pipeline circuit architecture has power partitioned pipeline stages. The first pipeline stage is non-power-gated for fast response in processing input data after receipt of a valid data signal. A power-gated second pipeline stage has two power-gated modes. Normally the power rail in the power-gated second pipeline stage is charged to a first voltage potential of a pipeline power supply. In the first power gated mode, the power rail is charged to a threshold voltage below the first voltage potential to reduce leakage. In the second power gated mode. the power rail is decoupled from the first voltage potential. A power-gated third pipeline stage has its power rail either coupled to the first voltage potential or power-gated where its power rail is decoupled from the first voltage potential. The power rail of the second power-gated pipeline stage charges to the first voltage potential before the third power-gated pipeline stage.
    Type: Application
    Filed: September 16, 2004
    Publication date: March 16, 2006
    Applicant: International Business Machines Corporation
    Inventors: Hung Ngo, Jente Kuang, Kevin Nowka, Rajiv Joshi
  • Publication number: 20060024852
    Abstract: Disclosed is a temperature sensor for an integrated circuit having at least one field effect transistor (FET) having a polysilicon gate, in which a current and a voltage is supplied to the polysilicon gate, changes in the current and the voltage of the polysilicon gate are monitored, wherein the polysilicon gate of the at least one FET is electrically isolated from other components of the integrated circuit, and the changes in the current or voltage are used to calculate a change in resistance of the polysilicon gate, and the change in resistance of the polysilicon gate is used to calculate a temperature change within the integrated circuit.
    Type: Application
    Filed: July 27, 2004
    Publication date: February 2, 2006
    Inventors: Rajiv Joshi, Sukhvinder Kang
  • Publication number: 20060014356
    Abstract: A metal-insulator-metal (MIM) capacitor including a metal layer, an insulating layer formed on the metal layer, at least a first opening and at least a second opening formed in the first insultaing layer, a dielectric layer formed in the first opening, a conductive material deposited in the first and second openings, and a first metal plate formed over the first opening and a second metal plate formed over the second opening. A method for fabricating the MIM capacitor, includes forming the first metal layer, forming the insulating layer on the first metal layer, forming at least the first opening and at least the second opening in the first insultaing layer, depositing a mask over the second opening, forming the dielectric layer in the first opening, removing the mask, depositing the conductive material in the first and second openings, and depositing a second metal layer over the first and second openings.
    Type: Application
    Filed: August 17, 2005
    Publication date: January 19, 2006
    Inventors: Louis Hsu, Rajiv Joshi, Chun-Yung Sung
  • Publication number: 20050275977
    Abstract: There is provided a method for managing a multi-level power supply. The method includes comparing a voltage level (Vs1) of a lower voltage supply bus to a voltage level (Vs2) of a higher voltage supply bus, and routing current from the lower voltage supply bus to the higher voltage supply bus if Vs2<Vs1. The lower and higher voltage supply busses provide power to a complementary metal oxide semiconductor (CMOS) circuit. The method prevents a latch-up of the CMOS circuit. There is also provided a circuit that employs the method.
    Type: Application
    Filed: June 14, 2004
    Publication date: December 15, 2005
    Inventors: Rajiv Joshi, Louis Hsu
  • Publication number: 20050260801
    Abstract: A field effect transistor (FET), integrated circuit (IC) chip including the FETs and a method of forming the FETs. The FETs include a thin channel with raised source/drain (RSD) regions at each end on an insulator layer, e.g., on an ultra-thin silicon on insulator (SOI) chip. Isolation trenches at each end of the FETs, i.e., at the end of the RSD regions, isolate and define FET islands. Insulating sidewalls at each RSD region sandwich the FET gate between the RSD regions. The gate dielectric may be a high K dielectric. Salicide on the RSD regions and, optionally, on the gates reduce device resistances.
    Type: Application
    Filed: November 24, 2004
    Publication date: November 24, 2005
    Inventors: Rama Divakaruni, Louis Hsu, Rajiv Joshi, Carl Radens
  • Publication number: 20050218427
    Abstract: A channel 16 of a FinFET 10 has a channel core 24 and a channel envelope 32, each made from a semiconductor material defining a different lattice structure to exploit strained silicon properties. A gate is coupled to the channel envelope through a gate dielectric. Exemplary materials are Si and SixGe1-x, wherein 78<x<92. The channel core 24 has a top surface 26 of width wc and an upstanding surface 28, 30 of height hc, preferably oriented 90° to one another. The channel envelope 32 is in contact with the top 26 and upstanding surfaces 28, 30 so that the area of interface is increased as compared to contact only along the top surface 26, improving electrical conductivity and gate 18 control over the channel 16. The height hc can be tailored to enable a smaller scale FET 10 within a stabilized SRAM. Various methods of making the channel 16 are disclosed, including a mask and etch method, a handle wafer/carrier wafer method, and a shallow trench method.
    Type: Application
    Filed: May 24, 2005
    Publication date: October 6, 2005
    Inventors: Rajiv Joshi, Richard Williams
  • Publication number: 20050199977
    Abstract: A method (and structure) that selectively forms a dielectric chamber on an electronic device by forming a dummy structure over a semiconductor substrate, depositing a dielectric layer over the dummy structure, forming an opening through the dielectric layer to the dummy structure, and removing the dummy structure to form the dielectric chamber.
    Type: Application
    Filed: May 16, 2005
    Publication date: September 15, 2005
    Applicant: International Business Machines Corporation
    Inventors: George Feng, Louis Hsu, Rajiv Joshi
  • Publication number: 20050128855
    Abstract: Bit and write decode/drivers, a random access memory (RAM) including the decode/drivers and an IC with a static RAM (SRAM) including the decode/drivers. The decode/drivers are clocked by a local clock and each produce access pulses wider than corresponding clock pulses. The bit decode/driver produces bit select pulses that are wider than a word select pulse and the write decode/driver produces write pulses that are wider than the bit select pulses for stable self timed RAM write accesses.
    Type: Application
    Filed: December 15, 2003
    Publication date: June 16, 2005
    Inventors: Rajiv Joshi, Arthur Tuminaro
  • Publication number: 20050127937
    Abstract: An integrated circuit (IC), random access memory on an IC and method of neutralizing device floating body effects. A floating body effect monitor monitors circuit/array activity and selectively provides an indication of floating body effect manifestation from inactivity, including the lapse of time since the most recent activity or memory access. A pulse generator generates a neutralization pulse in response to an indication of inactivity. A neutralization pulse distribution circuit passes the neutralization pulse to blocks in the circuit path or to array cells.
    Type: Application
    Filed: December 15, 2003
    Publication date: June 16, 2005
    Inventors: William Dachtera, Louis Hsu, Rajiv Joshi
  • Publication number: 20050122801
    Abstract: A row redundancy system is provided for replacing faulty wordlines of a memory array having a plurality of banks. The row redundancy system includes a remote fuse bay storing at least one faulty address corresponding to a faulty wordline of the memory array; a row fuse array for storing row fuse information corresponding to at least one bank of the memory array; and a copy logic module for copying at least one faulty address stored in the remote fuse bay into the row fuse array; wherein the copy logic module is programmed to copy the at least one faulty address into the row fuse information stored in the row fuse array corresponding to a predetermined number of banks in accordance with a selectable repair field size.
    Type: Application
    Filed: January 7, 2005
    Publication date: June 9, 2005
    Applicant: International Business Machines Corporation
    Inventors: Louis Hsu, Gregory Fredeman, Rajiv Joshi, Toshiaki Kirihata
  • Publication number: 20050110519
    Abstract: A level converter for interfacing two circuits supplied by different supply voltages, and integrated circuit including the level converter interfacing circuit in two different voltage islands. A first buffer is supplied by a virtual supply and receives an input signal from a lower voltage circuit. The first buffer drives a second buffer, which is supplied by a higher supply voltage. An output from the second buffer switches a supply select to selectively pass the higher supply voltage or a reduced supply voltage to the first buffer.
    Type: Application
    Filed: November 24, 2003
    Publication date: May 26, 2005
    Inventors: Anthony Correale, Rajiv Joshi, David Kung, Zhigang Pan, Ruchir Puri