Patents by Inventor Madhukar Vora

Madhukar Vora 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: 20080093636
    Abstract: A scalable device structure and process for forming a normally off JFET with 45 NM linewidths or less. The contacts to the source, drain and gate areas are formed by forming a layer of oxide of a thickness of less than 1000 angstroms, and, preferably 500 angstroms or less on top of the substrate. A nitride layer is formed on top of the oxide layer and holes are etched for the source, drain and gate contacts. A layer of polysilicon is then deposited so as to fill the holes and the polysilicon is polished back to planarize it flush with the nitride layer. The polysilicon contacts are then implanted with the types of impurities necessary for the channel type of the desired transistor and the impurities are driven into the semiconductor substrate below to form source, drain and gate regions.
    Type: Application
    Filed: December 20, 2007
    Publication date: April 24, 2008
    Inventors: Madhukar Vora, Ashok Kapoor
  • Publication number: 20070194416
    Abstract: Self-alignment structures, such as micro-balls and V-grooves, may be formed on chips made by different processes. The self-alignment structures may be aligned to mask layers within an accuracy of one-half the smallest feature size inside a chip. For example, the alignment structures can align an array of pads having a pitch of 0.6 microns, compared to a pitch of 100 microns available with today's Ball Grid Array (BGA) technology. As a result, circuits in the mated chips can communicate via the pads with the same speed or clock frequency as if in a single chip. For example, clock rates between interconnected chips can be increased from 100 MHz to 4 GHz due to low capacitance of the interconnected pads. Because high-density arrays of pads can interconnect chips, chips can be made smaller, thereby reducing cost of chips by order(s) of magnitude.
    Type: Application
    Filed: August 21, 2006
    Publication date: August 23, 2007
    Inventor: Madhukar Vora
  • Publication number: 20070042529
    Abstract: Self-alignment structures, such as micro-balls and V-grooves, may be formed on chips made by different processes. The self-alignment structures may be aligned to mask layers within an accuracy of one-half the smallest feature size inside a chip. For example, the alignment structures can align an array of pads having a pitch of 0.6 microns, compared to a pitch of 100 microns available with today's Ball Grid Array (BGA) technology. As a result, circuits in the mated chips can communicate via the pads with the same speed or clock frequency as if in a single chip. For example, clock rates between interconnected chips can be increased from 100 MHz to 4 GHz due to low capacitance of the interconnected pads. Because high-density arrays of pads can interconnect chips, chips can be made smaller, thereby reducing cost of chips by order(s) of magnitude.
    Type: Application
    Filed: August 21, 2006
    Publication date: February 22, 2007
    Inventor: Madhukar Vora
  • Publication number: 20070004134
    Abstract: A nonvolative memory in the form of a vertifcal flash EPROM with high density and low cost. A vertical MOS transistor is formed in well etched into a semiconductor substrate, the substrate having source, body and drain regions formed by ion implantation. A thin gate oxide or oxide-nitride-oxide (ONO) layer is formed in the well and a self-aligned floating gate of polysilicon is formed over the gate oxide in the well to overlie the body region. An anisotropic etch is used to form the self aligned floating gate so as to remove all horizontal components and leave no portion of said floating gate extending beyond the perimeter of said well such that its lateral extents are determined by the anisotropic etch and not photolithography. Leff is determined by the energy of the implants used for form the source and drain regions and not by lithography. A deep field oxide bounding parts of said well keeps the coupling ratio good at all feature sizes. A vertically oriented NMOS and PMOS transistor are also disclosed.
    Type: Application
    Filed: March 17, 2005
    Publication date: January 4, 2007
    Inventor: Madhukar Vora
  • Patent number: 6025736
    Abstract: A high speed active link switching technology suitable for implementing field programmable gate arrays using current mode logic in the high speed data path, and CMOS steering logic outside the high speed data path to enable the high speed switching logic and to implement multiplexer, selector and crossbar switch functions. High speed emitter follower logic compatible with the high speed switching logic for level shifting, buffering, and providing more current sink or source capacity is also disclosed. An advantage of the active link technology disclosed herein is that the active links do not degrade rise and fall times of high speed data signals nearly as much as the passive links of prior art field programmable gate arrays thereby enabling use of FPGAs in higher speed applications than was previously possible.
    Type: Grant
    Filed: June 4, 1997
    Date of Patent: February 15, 2000
    Assignee: Dynalogic
    Inventors: Madhukar Vora, Burnell G. West
  • Patent number: 6002268
    Abstract: An interface circuit for use in the layout of padframe interface circuits for field programmable gate arrays having a plurality of I/O cells each of which may be programmed as an input or an output (or both) and a programmable connection matrix which provide programmable pathways between the data output signals generated by the core array of logic blocks and I/O cells programmed as outputs and provide programmable pathways between I/O cells programmed as inputs and data input conductors going into the core array. The interface circuits are all substantially identical in structure, and each includes a sufficient number of power and ground connections to supply adequate current to the number of I/O cells the interface has. Each interface circuit also includes at least one and preferably two open spaces into which conductive paths may be laid out to carry power to the core array or carry dedicated signals to circuits other than the core which also reside on the integrated circuit.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: December 14, 1999
    Assignee: DynaChip Corporation
    Inventors: Paul Takao Sasaki, Madhukar Vora, Burnell G West
  • Patent number: 5229307
    Abstract: There is disclosed a process for making high performance bipolar and high performance MOS devices on the same integrated circuit die. The process comprises forming isolation islands of epitaxial silicon surrounded by field oxide and forming MOS transistors having polysilicon gates in some islands and forming bipolar transistors having polysilicon emitters in other islands. Insulating spacers are then formed around the edges of the polysilicon electrodes by anisotropically etching a layer of insulation material, usually thermally grown silicon dioxide covered with additional oxide deposited by CVD. A layer of refractory metal, preferably titanium covered with tungsten, is then deposited and heat treated at a temperature high enough to form only titanium disilicide to form silicide over the tops of the polysilicon electrodes and on top of the bases, sources and drains.
    Type: Grant
    Filed: December 19, 1990
    Date of Patent: July 20, 1993
    Assignee: National Semiconductor Corporation
    Inventors: Madhukar Vora, Gregory N. Burton, Ashok K. Kapoor
  • Patent number: 5227316
    Abstract: There is disclosed herein a bipolar transistor structure having a self aligned extended silicide base contact. The contact extends to the position of a base contact window located outside the perimeter of the isolation island on a contact pad formed over the field oxide. This allows the size of the isolation island to be kept smaller and allows a smaller extrinsic base region to be formed. The base contact is formed of titanium and titanium silicide where the titanium/silicide boundary is self aligned with the edge of the device isolation island. The silicide is formed by reacting the titanium which completely covers the exposed epitaxial silicon inside the isolation island. An anisotropically etched oxide sidewall spacer insulates the silicide from the sidewall of the silicide-covered, polysilicon emitter contact.
    Type: Grant
    Filed: August 12, 1991
    Date of Patent: July 13, 1993
    Assignee: National Semiconductor Corporation
    Inventors: Madhukar Vora, Greg Burton, Ashok Kapoor
  • Patent number: 5061986
    Abstract: There is disclosed herein a bipolar transistor structure having a self aligned extended silicide base contact. The contact extends to the position of a base contact window located outside the perimeter of the isolation island on a contact pad formed over the field oxide. This allows the size of the isolation island to be kept smaller and allows a smaller extrinsic base regions to be formed. The base contact is formed of titanium and titanium silicide where the titanium/silicide boundary is self aligned with the edge of the device isolation island. The silicide is formed by reacting the titanium which completely covers the exposed epitaxial silicon inside the isolation island. An anisotropically etched oxide sidewall spacer insulates the silicide from the sidewall of the silicide-covered, polysilicon emitter contact.
    Type: Grant
    Filed: February 5, 1990
    Date of Patent: October 29, 1991
    Assignee: National Semiconductor Corporation
    Inventors: Madhukar Vora, Greg Burton, Ashok Kapoor