Patents by Inventor Sankara Narayanan Ekkanath Madathil

Sankara Narayanan Ekkanath Madathil 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).

  • Patent number: 9087889
    Abstract: A semiconductor device comprises three semiconductor layers. The semiconductor layers are arranged to form a 2DHG and a 2DEG separated by a polarization layer. The device comprises a plurality of electrodes: first and second electrodes electrically connected to the 2DHG so that current can flow between them via the 2DHG and a third electrode electrically connected to the 2DEG so that when a positive voltage is applied to the third electrode, with respect to at least one of the other electrodes, the 2DEG and the 2DHG will be at least partially depleted.
    Type: Grant
    Filed: June 7, 2011
    Date of Patent: July 21, 2015
    Assignee: The University of Sheffield
    Inventors: Akira Nakajima, Sankara Narayanan Ekkanath Madathil
  • Patent number: 8785976
    Abstract: A low-loss GaN-based semiconductor device is provided. The semiconductor device has the InzGa1-zN layer (where 0?z<1), the AlxGa1-xN layer (where 0<x<1), the InyGa1-yN layer (where 0?y<1) and the p-type InwGa1-wN layer (where 0?w<1) which are sequentially stacked on a base substrate of a C-plane sapphire substrate, etc. At a non-operating time, the two-dimensional hole gas is formed in the InyGa1-yN layer in the vicinity part of a hetero-interface between the AlxGa1-xN layer and the InyGa1-yN layer, and the two-dimensional electron gas is formed in the InzGa1-zN layer in the vicinity part of a hetero-interface between the InzGa1-zN layer and the AlxGa1-xN layer.
    Type: Grant
    Filed: June 21, 2011
    Date of Patent: July 22, 2014
    Assignees: The University of Sheffield, Powdec K.K.
    Inventors: Akira Nakajima, Sankara Narayanan Ekkanath Madathil, Yasunobu Sumida, Hiroji Kawai
  • Publication number: 20130221409
    Abstract: A semiconductor device comprises three semiconductor layers. The semiconductor layers are arranged to form a 2DHG and a 2DEG separated by a polarization layer. The device comprises a plurality of electrodes: first and second electrodes electrically connected to the 2DHG so that current can flow between them via the 2DHG and a third electrode electrically connected to the 2DEG so that when a positive voltage is applied to the third electrode, with respect to at least one of the other electrodes, the 2DEG and the 2DHG will be at least partially depleted.
    Type: Application
    Filed: June 7, 2011
    Publication date: August 29, 2013
    Applicant: THE UNIVERSITY OF SHEFFIELD
    Inventors: Akira Nakajima, Sankara Narayanan Ekkanath Madathil
  • Publication number: 20130126942
    Abstract: A low-loss GaN-based semiconductor device is provided. The semiconductor device has the InzGa1-zN layer (where 0?z<1), the AlxGa1-xN layer (where 0<x<1), the InyGa1-yN layer (where 0?y<1) and the p-type InwGa1-wN layer (where 0?w<1) which are sequentially stacked on a base substrate of a C-plane sapphire substrate, etc. At a non-operating time, the two-dimensional hole gas 15 is formed in the InyGa1-yN layer in the vicinity part of a hetero-interface between the AlxGa1-xN layer and the InyGa1-yN layer, and the two-dimensional electron gases is formed in the InzGa1-zN layer in the vicinity part of a hetero-interface between the InzGa1-zN layer and the AlxGa1-xN layer.
    Type: Application
    Filed: June 21, 2011
    Publication date: May 23, 2013
    Applicants: POWDEC K.K., THE UNIVERSITY OF SHEFFIELD
    Inventors: Akira Nakajima, Sankara Narayanan Ekkanath Madathil, Yasunobu Sumida, Hiroji Kawai
  • Patent number: 7893457
    Abstract: A semiconductor device includes at least one cell including a base region of a first conductivity type having disposed therein at least one emitter region of a second conductivity type, a first well region of a second conductivity type, a second well region of a first conductivity type, a drift region of a second conductivity type, a collector region of a first conductivity type, and a collector contact. Each cell is disposed within the first well region, and the first well region is disposed within the second well region. The device further includes a first gate in communication with a base region so that a MOSFET channel can be formed between an emitter region and the first well region, and at least one embedded region embedded in the first well region. The device is configured such that during operation of the device a depletion region at a junction between the base region and the first well region can extend to a junction between the first well region and the second well region.
    Type: Grant
    Filed: August 10, 2005
    Date of Patent: February 22, 2011
    Assignee: ECO Semiconductors Ltd.
    Inventors: Sankara Narayanan Ekkanath Madathil, Mark Robert Sweet, Konstantin Vladislavovich Vershinin
  • Publication number: 20090159928
    Abstract: A power semiconductor device including source and drain regions located in a lateral arrangement in a first portion of the device, and at least one current providing cell located in a second portion of the device and spaced apart from the first portion at least by a substrate region of a first conductivity type.
    Type: Application
    Filed: October 16, 2006
    Publication date: June 25, 2009
    Applicant: ECO SEMICONDUCTORS LTD
    Inventors: Sankara Narayanan Ekkanath Madathil, David William Green
  • Publication number: 20080191238
    Abstract: According to the invention there is provided a semiconductor device including: at least one cell including a base region of a first conductivity type having disposed therein at least one emitter region of a second conductivity type; a first well region of a second conductivity type; a second well region of a first conductivity type; a drift region of a second conductivity type; a collector region of a first conductivity type; a collector contact; in which each cell is disposed within the first well region and the first well region is disposed within the second well region; the device further including: a first gate in communication with a base region so that a MOSFET channel can be formed between an emitter region and the first well region; and at least one embedded region embedded in the first well region; in which the device is configured such that during operation of the device a depletion region at a junction between the base region and the first well region can extend to a junction between the first well
    Type: Application
    Filed: August 10, 2005
    Publication date: August 14, 2008
    Applicant: ECO SEMICONDUCTORS LIMITED
    Inventors: Sankara Narayanan Ekkanath Madathil, Mark Robert Sweet, Konstantin Vladislavovich Vershinin
  • Patent number: 6724043
    Abstract: There is disclosed a semiconductor device comprising: at least one cell comprising a base region (32) of a first conductivity type having disposed therein at least one emitter region (36a, 36b) of a second conductivity type; a first well region (22) of a second conductivity type; a second well region (2a) of a first conductivity type; a drift region (24) of a second conductivity type; a collector region (14) of a first conductivity type; a collector contact (16) in which each cell is disposed within the first well region (22) and the first well region (22) is disposed within the second well-region (20); the device further comprising: a first gate (61) disposed over a base region (32) so that a MOSFET channel can be formed between an emitter region (36a, 36b) and the first well region (22); the device further comprising: a second gate disposer over the second well region (20) so that a MOSFET channel can be formed between the first well region (22) and the drift region (24).
    Type: Grant
    Filed: August 22, 2002
    Date of Patent: April 20, 2004
    Assignee: De Montfort University
    Inventor: Sankara Narayanan Ekkanath Madathil