Patents by Inventor Alexander Lidow

Alexander Lidow 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: 20160035847
    Abstract: An enhancement-mode GaN transistor with reduced gate leakage current between a gate contact and a 2DEG region and a method for manufacturing the same. The enhancement-mode GaN transistor including a GaN layer, a barrier layer disposed on the GaN layer with a 2DEG region formed at an interface between the GaN layer and the barrier layer, and source contact and drain contacts disposed on the barrier layer. The GaN transistor further includes a p-type gate material formed above the barrier layer and between the source and drain contacts and a gate metal disposed on the p-type gate material, with wherein the p-type gate material including comprises a pair of self-aligned ledges that extend toward the source contact and drain contact, respectively.
    Type: Application
    Filed: July 30, 2014
    Publication date: February 4, 2016
    Inventors: Jianjun Cao, Alexander Lidow, Alana Nakata
  • Patent number: 9214528
    Abstract: A method for forming an enhancement mode GaN HFET device with an isolation area that is self-aligned to a contact opening or metal mask window. Advantageously, the method does not require a dedicated isolation mask and the associated process steps, thus reducing manufacturing costs. The method includes providing an EPI structure including a substrate, a buffer layer a GaN layer and a barrier layer. A dielectric layer is formed over the barrier layer and openings are formed in the dielectric layer for device contact openings and an isolation contact opening. A metal layer is then formed over the dielectric layer and a photoresist film is deposited above each of the device contact openings. The metal layer is then etched to form a metal mask window above the isolation contact opening and the barrier and GaN layer are etched at the portion that is exposed by the isolation contact opening in the dielectric layer.
    Type: Grant
    Filed: July 2, 2014
    Date of Patent: December 15, 2015
    Assignee: Efficient Power Conversion Corporation
    Inventors: Chunhua Zhou, Jianjun Cao, Alexander Lidow, Robert Beach, Alana Nakata, Robert Strittmatter, Guangyuan Zhao, Seshadri Kolluri, Yanping Ma, Fang Chang Liu, Ming-Kun Chiang, Jiali Cao
  • Patent number: 9214399
    Abstract: An integrated circuit having a substrate, a buffer layer formed over the substrate, a barrier layer formed over the buffer layer, and an isolation region that isolates an enhancement mode device from a depletion mode device. The integrated circuit further includes a first gate contact for the enhancement mode device that is disposed in one gate contact recess and a second gate contact for the depletion mode device that is disposed in a second gate contact recess.
    Type: Grant
    Filed: July 30, 2014
    Date of Patent: December 15, 2015
    Assignee: Efficient Power Conversion Corporation
    Inventors: Jianjun Cao, Robert Beach, Alexander Lidow, Alana Nakata, Robert Strittmatter, Guangyuan Zhao, Yanping Ma, Chunhua Zhou, Seshadri Kolluri, Fang Chang Liu, Ming-Kun Chiang, Jiali Cao, Agus Jauhar
  • Patent number: 9214461
    Abstract: A GaN transistor with polysilicon layers for creating additional components for an integrated circuit. The GaN device includes an EPI structure and an insulating material disposed over EPI structure. Furthermore, one or more polysilicon layers are disposed in the insulating material with the polysilicon layers having one or more n-type regions and p-type regions. The device further includes metal interconnects disposed on the insulating material and vias disposed in the insulating material layer that connect source and drain metals to the n-type and p-type regions of the polysilicon layer.
    Type: Grant
    Filed: July 29, 2014
    Date of Patent: December 15, 2015
    Assignee: Efficient Power Coversion Corporation
    Inventors: Jianjun Cao, Robert Beach, Alexander Lidow, Alana Nakata, Guangyuan Zhao, Yanping Ma, Robert Strittmatter, Michael A. De Rooji, Chunhua Zhou, Seshadri Kolluri, Fang Chang Liu, Ming-Kun Chiang, Jiali Cao, Agus Jauhar
  • Patent number: 9171911
    Abstract: An integrated semiconductor device which includes a substrate layer, a buffer layer formed on the substrate layer, a gallium nitride layer formed on the buffer layer, and a barrier layer formed on the gallium nitride layer. Ohmic contacts for a plurality of transistor devices are formed on the barrier layer. Specifically, a plurality of first ohmic contacts for the first transistor device are formed on a first portion of the surface of the barrier layer, and a plurality of second ohmic contacts for the second transistor device are formed on a second portion of the surface of the barrier layer. In addition, one or more gate structures formed on a third portion of the surface of the barrier between the first and second transistor devices. Preferably, the one or more gate structures and the spaces between the gate structures and the source contacts of the transistor devices collectively form an isolation region that electrically isolates the first transistor device from the second transistor device.
    Type: Grant
    Filed: July 2, 2014
    Date of Patent: October 27, 2015
    Assignee: Efficient Power Conversion Corporation
    Inventors: Chunhua Zhou, Jianjun Cao, Alexander Lidow, Robert Beach, Alana Nakata, Robert Strittmatter, Guangyuan Zhao, Seshadri Kolluri, Yanping Ma, Fang Chang Liu, Ming-Kun Chiang, Jiali Cao
  • Patent number: 8969918
    Abstract: An enhancement mode GaN transistor having a gate pGaN structure having a thickness which avoids dielectric failure. In one embodiment, this thickness is in the range of 400 ? to 900 ?. In a preferred embodiment, the thickness is 600 ?.
    Type: Grant
    Filed: April 8, 2010
    Date of Patent: March 3, 2015
    Assignee: Efficient Power Conversion Corporation
    Inventors: Alexander Lidow, Robert Beach, Alana Nakata, Jianjun Cao, Guang Yuan Zhao
  • Publication number: 20150034962
    Abstract: An integrated circuit having a substrate, a buffer layer formed over the substrate, a barrier layer formed over the buffer layer, and an isolation region that isolates an enhancement mode device from a depletion mode device. The integrated circuit further includes a first gate contact for the enhancement mode device that is disposed in one gate contact recess and a second gate contact for the depletion mode device that is disposed in a second gate contact recess.
    Type: Application
    Filed: July 30, 2014
    Publication date: February 5, 2015
    Inventors: Jianjun Cao, Robert Beach, Alexander Lidow, Alana Nakata, Robert Strittmatter, Guangyuan Zhao, Yanping Ma, Chunhua Zhou, Seshadri Kolluri, Fang Chang Liu, Ming-Kun Chiang, Jiali Cao, Agus Jauhar
  • Publication number: 20150028384
    Abstract: A GaN transistor with polysilicon layers for creating additional components for an integrated circuit and a method for manufacturing the same. The GaN device includes an EPI structure and an insulating material disposed over EPI structure. Furthermore, one or more polysilicon layers are disposed in the insulating material with the polysilicon layers having one or more n-type regions and p-type regions. The device further includes metal interconnects disposed on the insulating material and vias disposed in the insulating material layer that connect source and drain metals to the n-type and p-type regions of the polysilicon layer.
    Type: Application
    Filed: July 29, 2014
    Publication date: January 29, 2015
    Inventors: Jianjun Cao, Robert Beach, Alexander Lidow, Alana Nakata, Guangyuan Zhao, Yanping Ma, Robert Strittmatter, Michael A. De Rooji, Chunhua Zhou, Seshadri Kolluri, Fang Chang Liu, Ming-Kun Chiang, Jiali Cao, Agus Jauhar
  • Publication number: 20150008442
    Abstract: An integrated semiconductor device which includes a substrate layer, a buffer layer formed on the substrate layer, a gallium nitride layer formed on the buffer layer, and a barrier layer formed on the gallium nitride layer. Ohmic contacts for a plurality of transistor devices are formed on the barrier layer. Specifically, a plurality of first ohmic contacts for the first transistor device are formed on a first portion of the surface of the barrier layer, and a plurality of second ohmic contacts for the second transistor device are formed on a second portion of the surface of the barrier layer. In addition, one or more gate structures formed on a third portion of the surface of the barrier between the first and second transistor devices. Preferably, the one or more gate structures and the spaces between the gate structures and the source contacts of the transistor devices collectively form an isolation region that electrically isolates the first transistor device from the second transistor device.
    Type: Application
    Filed: July 2, 2014
    Publication date: January 8, 2015
    Inventors: Chunhua Zhou, Jianjun Cao, Alexander Lidow, Robert Beach, Alana Nakata, Robert Strittmatter, Guang Yuan Zhao, Seshadri Kolluri, Yanping Ma, Fang Chang, Ming-Kun Chiang, Jiali Cao
  • Publication number: 20150011057
    Abstract: A method for forming an enhancement mode GaN HFET device with an isolation area that is self-aligned to a contact opening or metal mask window. Advantageously, the method does not require a dedicated isolation mask and the associated process steps, thus reducing manufacturing costs. The method includes providing an EPI structure including a substrate, a buffer layer a GaN layer and a barrier layer. A dielectric layer is formed over the barrier layer and openings are formed in the dielectric layer for device contact openings and an isolation contact opening. A metal layer is then formed over the dielectric layer and a photoresist film is deposited above each of the device contact openings. The metal layer is then etched to form a metal mask window above the isolation contact opening and the barrier and GaN layer are etched at the portion that is exposed by the isolation contact opening in the dielectric layer.
    Type: Application
    Filed: July 2, 2014
    Publication date: January 8, 2015
    Inventors: Chunhua Zhou, Jianjun Cao, Alexander Lidow, Robert Beach, Alana Nakata, Robert Strittmatter, Guang Yuan Zhao, Seshadri Kolluri, Yanping Ma, Fang Chang Liu, Ming-Kun Chiang, Jiali Cao
  • Patent number: 8890168
    Abstract: An enhancement-mode GaN transistor. The enhancement-mode GaN transistor includes a substrate, transition layers, a buffer layer comprised of a III Nitride material, a barrier layer comprised of a III Nitride material, drain and source contacts, a gate III-V compound containing acceptor type dopant elements, and a gate metal, where the gate III-V compound and the gate metal are formed with a single photo mask process to be self-aligned and the bottom of the gate metal and the top of the gate compound have the same dimension. The enhancement mode GaN transistor may also have a field plate made of Ohmic metal, where a drain Ohmic metal, a source Ohmic metal, and the field plate are formed by a single photo mask process.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: November 18, 2014
    Assignee: Efficient Power Conversion Corporation
    Inventors: Alexander Lidow, Robert Beach, Alana Nakata, Jianjun Cao, Guang Yuang Zhao
  • Patent number: 8853749
    Abstract: A self-aligned transistor gate structure that includes an ion-implanted portion of gate material surrounded by non-implanted gate material on each side. The gate structure may be formed, for example, by applying a layer of GaN material over an AlGaN barrier layer and implanting a portion of the GaN layer to create the gate structure that is laterally surrounded by the GaN layer.
    Type: Grant
    Filed: January 31, 2012
    Date of Patent: October 7, 2014
    Assignee: Efficient Power Conversion Corporation
    Inventors: Alexander Lidow, Jianjun Cao, Robert Beach, Robert Strittmatter, Guang Y. Zhao, Alana Nakata
  • Patent number: 8823012
    Abstract: Enhancement-mode GaN devices having a gate spacer, a gate metal material and a gate compound that are self-aligned, and a methods of forming the same. The materials are patterned and etched using a single photo mask, which reduces manufacturing costs. An interface of the gate spacer and the gate compound has lower leakage than the interface of a dielectric film and the gate compound, thereby reducing gate leakage. In addition, an ohmic contact metal layer is used as a field plate to relieve the electric field at a doped III-V gate compound corner towards the drain contact, which leads to lower gate leakage current and improved gate reliability.
    Type: Grant
    Filed: February 23, 2012
    Date of Patent: September 2, 2014
    Assignee: Efficient Power Conversion Corporation
    Inventors: Alexander Lidow, Robert Beach, Alana Nakata, Jianjun Cao, Guang Yuan Zhao, Robert Strittmatter, Fang Chang Liu
  • Patent number: 8785974
    Abstract: A semiconductor device comprising a silicon substrate, a compound semiconductor material, an insulating material between the silicon substrate and the compound semiconductor material, and a top surface comprising means of electrical connection, and passivation material, where the passivation material is silicon nitride, silicon dioxide, or a combination of both. The present invention eliminates the need for a thick electrical insulator between a heat sink and the back surface of a surface mounted device by the inclusion of an AlN seed layer to electrically isolate the silicon substrate of the device. The sidewalls of the device are also electrically isolated from the active area of the device.
    Type: Grant
    Filed: April 8, 2010
    Date of Patent: July 22, 2014
    Assignee: Efficient Power Conversion Corporation
    Inventors: Alexander Lidow, Robert Beach, Alana Nakata, Jianjun Cao
  • Publication number: 20130234153
    Abstract: An enhancement-mode GaN transistor. The enhancement-mode GaN transistor includes a substrate, transition layers, a buffer layer comprised of a III Nitride material, a barrier layer comprised of a III Nitride material, drain and source contacts, a gate III-V compound containing acceptor type dopant elements, and a gate metal, where the gate III-V compound and the gate metal are formed with a single photo mask process to be self-aligned and the bottom of the gate metal and the top of the gate compound have the same dimension. The enhancement mode GaN transistor may also have a field plate made of Ohmic metal, where a drain Ohmic metal, a source Ohmic metal, and the field plate are formed by a single photo mask process.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 12, 2013
    Applicant: Efficient Power Conversion Corporation
    Inventors: Alexander Lidow, Robert Beach, Alana Nakata, Jianjun Cao, Guang Yuang Zhao
  • Patent number: 8436398
    Abstract: An enhancement-mode GaN transistor, the transistor having a substrate, transition layers, a buffer layer comprised of a III Nitride material, a barrier layer comprised of a III Nitride material, drain and source contacts, a gate containing acceptor type dopant elements, and a diffusion barrier comprised of a III Nitride material between the gate and the buffer layer.
    Type: Grant
    Filed: April 7, 2010
    Date of Patent: May 7, 2013
    Assignee: Efficient Power Conversion Corporation
    Inventors: Alexander Lidow, Robert Beach, Guang Y. Zhao, Jianjun Cao
  • Patent number: 8404508
    Abstract: An enhancement-mode GaN transistor and a method of forming it. The enhancement-mode GaN transistor includes a substrate, transition layers, a buffer layer comprised of a III Nitride material, a barrier layer comprised of a III Nitride material, drain and source contacts, a gate III-V compound containing acceptor type dopant elements, and a gate metal, where the gate III-V compound and the gate metal are formed with a single photo mask process to be self-aligned and the bottom of the gate metal and the top of the gate compound have the same dimension. The enhancement mode GaN transistor may also have a field plate made of Ohmic metal, where a drain Ohmic metal, a source Ohmic metal, and the field plate are formed by a single photo mask process.
    Type: Grant
    Filed: April 8, 2010
    Date of Patent: March 26, 2013
    Assignee: Efficient Power Conversion Corporation
    Inventors: Alexander Lidow, Robert Beach, Alana Nakata, Jianjun Cao, Guang Yuan Zhao
  • Patent number: 8368120
    Abstract: A hybrid device including a silicon based MOSFET operatively connected with a GaN based device.
    Type: Grant
    Filed: September 2, 2011
    Date of Patent: February 5, 2013
    Assignee: International Rectifier Corporation
    Inventors: Alexander Lidow, Daniel M. Kinzer, Srikant Sridevan
  • Patent number: 8350294
    Abstract: A MISFET, such as a GaN transistor, with low gate leakage. In one embodiment, the gate leakage is reduced with a compensated GaN layer below the gate contact and above the barrier layer. In another embodiment, the gate leakage is reduced by employing a semi-insulating layer below the gate contact and above the barrier layer.
    Type: Grant
    Filed: April 8, 2010
    Date of Patent: January 8, 2013
    Assignee: Efficient Power Conversion Corporation
    Inventors: Alexander Lidow, Robert Beach, Jianjun Cao, Alana Nakata, Guang Yuan Zhao
  • Publication number: 20120193688
    Abstract: A self-aligned transistor gate structure that includes an ion-implanted portion of gate material surrounded by non-implanted gate material on each side. The gate structure may be formed, for example, by applying a layer of GaN material over an AlGaN barrier layer and implanting a portion of the GaN layer to create the gate structure that is laterally surrounded by the GaN layer.
    Type: Application
    Filed: January 31, 2012
    Publication date: August 2, 2012
    Inventors: Alexander Lidow, Jianjun Cao, Robert Beach, Robert Strittmatter, Guang Y. Zhao, Alana Nakata