Patents Assigned to SuVolta, Inc.
  • Publication number: 20110074498
    Abstract: A suite of novel structures and methods is provided to reduce power consumption in a wide array of electronic devices and systems. Some of these structures and methods can be implemented largely by reusing existing bulk CMOS process flows and manufacturing technology, allowing the semiconductor industry as well as the broader electronics industry to avoid a costly and risky switch to alternative technologies. As will be discussed, some of the structures and methods relate to a Deeply Depleted Channel (DDC) design, allowing CMOS based devices to have a reduced ?VT compared to conventional bulk CMOS and can allow the threshold voltage VT of FETs having dopants in the channel region to be set much more precisely. The DDC design also can have a strong body effect compared to conventional bulk CMOS transistors, which can allow for significant dynamic control of power consumption in DDC transistors.
    Type: Application
    Filed: February 18, 2010
    Publication date: March 31, 2011
    Applicant: SuVolta, Inc.
    Inventors: Scott E. Thompson, Damodar R. Thummalapally
  • Patent number: 7915107
    Abstract: This invention describes a method of building complementary logic circuits using junction field effect transistors in silicon. This invention is ideally suited for deep submicron dimensions, preferably below 65 nm. The basis of this invention is a complementary Junction Field Effect Transistor which is operated in the enhancement mode. The speed-power performance of the JFETs becomes comparable with the CMOS devices at sub-70 nanometer dimensions. However, the maximum power supply voltage for the JFETs is still limited to below the built-in potential (a diode drop). To satisfy certain applications which require interface to an external circuit driven to higher voltage levels, this invention includes the structures and methods to build CMOS devices on the same substrate as the JFET devices.
    Type: Grant
    Filed: June 26, 2009
    Date of Patent: March 29, 2011
    Assignee: SuVolta, Inc.
    Inventor: Ashok K. Kapoor
  • Publication number: 20100315128
    Abstract: Circuits using four terminal transistors are disclosed. Such circuits can include various static and dynamic logic circuits, flip-flops, multiplexer, tri-state driver, phase detector, logic having variable speeds of operation, and/or analog circuit with such four terminal transistors operating in a linear or nonlinear mode.
    Type: Application
    Filed: August 23, 2010
    Publication date: December 16, 2010
    Applicant: SUVOLTA, INC.
    Inventor: Ashok Kumar Kapoor
  • Patent number: 7847354
    Abstract: A semiconductor device comprises a partially depleted semiconductor-on-insulator structure having both a three terminal JFET and a four terminal JFET constructed thereon. The four terminal JFET comprises a source region, a drain region, a channel region, a front gate region, and a back gate region formed in a semiconductor layer of the partially depleted semiconductor-on-insulator structure. The three terminal JFET comprises a source region formed in the semiconductor layer of the partially depleted semiconductor-on-insulator structure, and a drain region spaced apart from the source region and formed in the semiconductor layer of the partially depleted semiconductor-on-insulator structure. The three terminal JFET further comprises a channel region between the source region and the drain region and formed in the semiconductor layer of the partially depleted semiconductor-on-insulator structure.
    Type: Grant
    Filed: February 6, 2009
    Date of Patent: December 7, 2010
    Assignee: SuVolta, Inc.
    Inventor: Damodar R. Thummalapally
  • Patent number: 7848130
    Abstract: A memory cell includes an access transistor, first and second pull-up transistors, first and second pull-down transistors, and a first search transistor. The access transistor is connected to a first word line and connected between a first bit line and a first data node. The first pull-up transistor is connected to a first power supply point and the first data node, and the second pull-up transistor is connected to the first power supply point and the second data node. The first pull-down transistor is connected to a second power supply point and the first data node, and the second pull-down transistor is connected to the second power supply point and the second data node. The first search transistor is connected to the second data node and includes a source terminal connected to a third power supply point comprising a voltage less than the voltage at the second power supply point.
    Type: Grant
    Filed: December 19, 2008
    Date of Patent: December 7, 2010
    Assignee: SuVolta, Inc.
    Inventors: Damodar R. Thummalapally, Richard K. Chou
  • Patent number: 7843721
    Abstract: A memory device including a static random access memory (SRAM) cell comprising junction field effect transistors (JFETs) has been disclosed. The memory cell includes a first bipolar junction transistor (BJT) for driving a bit line at logic levels having a potential outside the potential range in which the SRAM cell operates. An amplifier including a level translator circuit provides a level shifting operation on the data provided by the bit line to provide level shifted data having a voltage swing within the potential range in which the SRAM cell operates. The level translator circuit includes a second BJT. In this way, fast read operation of a SRAM cell comprising JFETs may be provided.
    Type: Grant
    Filed: September 18, 2008
    Date of Patent: November 30, 2010
    Assignee: SuVolta, Inc.
    Inventors: Richard K. Chou, Damodar R. Thummalapally
  • Patent number: 7843018
    Abstract: A transistor includes a channel region with a first portion and a second portion. A length of the first portion is smaller than a length of the second portion. The first portion has a higher threshold voltage than the second portion. The lower threshold voltage of the second portion allows for an increased ON current. Despite the increase attained in the ON current, the higher threshold voltage of the first portion maintains or lowers a relatively low OFF current for the transistor.
    Type: Grant
    Filed: February 2, 2009
    Date of Patent: November 30, 2010
    Assignee: SuVolta, Inc.
    Inventor: Sung-Ki Min
  • Patent number: 7804332
    Abstract: Circuits using four terminal junction field effect transistors (JFETs) are disclosed. Such circuits can include various static and dynamic logic circuits, flip-flops, multiplexer, tri-state driver, phase detector, logic having variable speeds of operation, and/or analog circuit with such four terminal JFETs operating in a linear or nonlinear mode.
    Type: Grant
    Filed: July 21, 2009
    Date of Patent: September 28, 2010
    Assignee: SuVolta, Inc.
    Inventor: Ashok Kumar Kapoor
  • Patent number: 7772620
    Abstract: A junction field effect transistor comprises a silicon-on-insulator architecture. A front gate region and a back gate region are formed in a silicon region of the SOI architecture. The silicon region has a thin depth such that the back gate region has a thin depth, and whereby a depletion region associated with the back gate region recedes substantially up to an insulating layer of the SOI architecture.
    Type: Grant
    Filed: July 25, 2008
    Date of Patent: August 10, 2010
    Assignee: SuVolta, Inc.
    Inventor: Ashok K. Kapoor
  • Patent number: 7772619
    Abstract: A semiconductor device includes a silicon on insulator (SOI) substrate, comprising an insulation layer formed on semiconductor material, and a fin structure. The fin structure is formed of semiconductor material and extends from the SOI substrate. Additionally, the fin structure includes a source region, a drain region, a channel region, and a gate region. The source region, drain region, and the channel region are doped with a first type of impurities, and the gate region is doped with a second type of impurities. The gate region abuts the channel region along at least one boundary, and the channel region is operable to conduct current between the drain region and the source region when the semiconductor device is operating in an on state.
    Type: Grant
    Filed: May 2, 2008
    Date of Patent: August 10, 2010
    Assignee: SuVolta, Inc.
    Inventor: Ashok K. Kapoor
  • Patent number: 7764137
    Abstract: A circuit can include an amplifier having at least a first junction field effect transistor (JFET) of a first conductivity type with a source coupled to a first power supply node, and a drain coupled to an amplifier output node. A first variable bias circuit can be coupled between the drain and at least one gate of the first JFET. The first variable bias circuit can alter a direct current (DC) bias to the first JFET according a potential at the amplifier output node. A first bias impedance can be coupled between the drain of the first JFET and a second power supply node. The circuit can also include a non-linear transmission line (NLTL) coupled between the amplifier output and a gate of the first JFET. The NLTL being configured to propagate an electrical soliton.
    Type: Grant
    Filed: September 21, 2007
    Date of Patent: July 27, 2010
    Assignee: SuVolta, Inc.
    Inventor: Christopher L. Hamlin
  • Patent number: 7750735
    Abstract: A voltage-level translator includes an input node, a differential amplifier, first and second output transistors, and a constant current source. The input node receives an input signal. The differential amplifier produces a voltage swing at an amplifier node based at least in part on a difference between the input signal and a voltage supply. The first output transistor provides a substantially constant current to the output node. The voltage swing produced by the differential amplifier prevents forward biasing of the second output transistor. The constant current source provides a substantially constant current both to the differential amplifier and through the first output transistor. The translator outputs a first voltage in an output voltage range at the output node when the input signal is at a high voltage, and outputs a second voltage in the output voltage range at the output node when the input signal is at a low voltage.
    Type: Grant
    Filed: July 11, 2008
    Date of Patent: July 6, 2010
    Assignee: SuVolta, Inc.
    Inventor: Abhijit Ray
  • Patent number: 7746146
    Abstract: A level shifting circuit can include a first input junction field effect transistor (JFET) having a gate coupled to receive an input signal having a first voltage swing that provides a controllable impedance path between a first supply node and a first terminal of a first bias stack including at least one JFET. A driver circuit can be coupled to receive an output from the first bias stack that provides a level shifted output having a second voltage swing that is less than the first voltage swing.
    Type: Grant
    Filed: September 1, 2006
    Date of Patent: June 29, 2010
    Assignee: SuVolta, Inc.
    Inventors: Richard K. Chou, Damodar R. Thummalapally
  • Patent number: 7742325
    Abstract: A method for operating an SRAM cell comprises, during a read operation, forward biasing an N-well of a first and second pull-up transistor, and forward biasing a P-well of a first and second pull-down transistor and a first and second access transistor. The method further comprises, during a write operation, zero or reverse biasing an N-well of a first and second pull-up transistor, and forward biasing a P-well of a first and second pull-down transistor and a first and second access transistor. The method further comprises, during an idle state, zero biasing an N-well of a first and second pull-up transistor and zero biasing a P-well of a first and second pull-down transistor and a first and second access transistor. In addition, one or more rows or columns of memory cells may receive a bias voltage.
    Type: Grant
    Filed: December 17, 2007
    Date of Patent: June 22, 2010
    Assignee: SuVolta, Inc.
    Inventor: Eric H. Voelkel
  • Patent number: 7741882
    Abstract: An output buffer circuit includes a first output transistor having a source terminal connected to a voltage supply and a drain terminal connected to an output node. The first output transistor is capable of coupling the output node to the voltage supply when the input signal is at a high voltage in the input voltage range. The circuit also includes a second output transistor having a drain terminal connected to the output node and a source terminal connected to ground. The second output transistor is capable of coupling the output node to ground when the input signal is at a low voltage in the input voltage range. The circuit further includes a current-limiting circuit coupled to a gate terminal of the first output transistor and capable of limiting a current flowing through the gate terminal when the first output transistor is turned on. The output node outputs an output signal in an output voltage range, wherein a high voltage of the output voltage range exceeds the high voltage of the input voltage range.
    Type: Grant
    Filed: July 15, 2008
    Date of Patent: June 22, 2010
    Assignee: SuVolta, Inc.
    Inventor: Abhijit Ray
  • Publication number: 20100149854
    Abstract: A method of fabricating an integrated circuit device storage cell may include forming a channel region comprising a semiconductor material doped to a first conductivity type; forming a store gate structure comprising a semiconductor material doped to a second conductivity type in contact with the channel region; and forming a control gate terminal from at least a portion of a semiconductor layer deposited on a substrate surface in contact with the channel region, the portion of the semiconductor layer being doped to the second conductivity type.
    Type: Application
    Filed: February 22, 2010
    Publication date: June 17, 2010
    Applicant: SUVOLTA, INC.
    Inventor: Madhu B. Vora
  • Patent number: 7736962
    Abstract: A junction field effect transistor comprises an insulating layer formed in a substrate. A source region of a first conductivity type is formed on the insulating layer, and a drain region of the first conductivity type is formed on the insulating layer and spaced apart from the drain region. A channel region of the first conductivity type is located between the source region and the drain region and formed on the insulating layer. A gate region of the second conductivity type surrounds all surfaces of a length of the channel region such that the channel region is embedded within the gate region.
    Type: Grant
    Filed: January 7, 2009
    Date of Patent: June 15, 2010
    Assignee: SuVolta, Inc.
    Inventor: Kiyoshi Mori
  • Patent number: 7729149
    Abstract: A semiconductor device that includes a memory cell having a junction field effect transistor (JFET) used to form a content addressable memory (CAM) cell is disclosed. The JFET may include a data storage region disposed between a first and second insulating region. The data storage region provides a first threshold voltage to the JFET when storing a first data value and provides a second threshold voltage to the JFET when storing a second data value. The memory cell is a dynamic random access memory (DRAM) cell and can be used to form a CAM cell. The CAM cell may be a ternary CAM cell formed with as few as two JFETs.
    Type: Grant
    Filed: May 1, 2007
    Date of Patent: June 1, 2010
    Assignee: SuVolta, Inc.
    Inventor: Damodar R. Thummalapally
  • Patent number: 7727821
    Abstract: An image sensing device can include one or more image sensing cells. Each image sensing cell can have a charge store element formed from a semiconductor material doped to a first conductivity type. The charge store element can be in contact with a channel region formed from a semiconductor material doped to a second conductivity type. The charge store element can have one or more surfaces for exposure to an image source. Each image sensing cell can also include a charge electrode formed from a semiconductor material doped to the first conductivity type that is separated from the charge store element by a semiconductor material doped to the second conductivity type. In addition, one or more current detection electrodes can be included in each image sensing cell. A current detection electrode can pass a current flowing through the channel region in a read operation. Such an image sensing cell can be compact in size and/or have a large image sensing area.
    Type: Grant
    Filed: May 1, 2007
    Date of Patent: June 1, 2010
    Assignee: SuVolta, Inc.
    Inventor: Madhu B. Vora
  • Patent number: 7713804
    Abstract: A JFET structure with self-aligned metal source, drain and gate contacts with very low resistivity and very small feature sizes. Small source, drain and gate openings are etched in a thin dielectric layer which has a thickness set according to the desired source, gate and drain opening sizes, said dielectric layer having a nitride top layer. Metal is deposited on top of said dielectric layer to fill said openings and the metal is polished back to the top of the dielectric layer to achieve thin source, drain and gate contacts. Some embodiments include an anti-leakage poly-silicon layer lining the contact holes and all embodiments where spiking may occur include a barrier metal layer.
    Type: Grant
    Filed: November 24, 2008
    Date of Patent: May 11, 2010
    Assignee: SuVolta, Inc.
    Inventors: Madhukar B. Vora, Ashok K. Kapoor