Patents by Inventor Sujit Banerjee

Sujit Banerjee 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: 20150214164
    Abstract: Semiconductor devices comprising a getter material are described. The getter material can be located in or over the active region of the device and/or in or over a termination region of the device. The getter material can be a conductive or an insulating material. The getter material can be present as a continuous or discontinuous film. The device can be a SiC semiconductor device such as a SiC vertical MOSFET. Methods of making the devices are also described. Semiconductor devices and methods of making the same comprising source ohmic contacts formed using a self-aligned process are also described. The source ohmic contacts can comprise titanium silicide and/or titanium silicide carbide and can act as a getter material.
    Type: Application
    Filed: April 7, 2015
    Publication date: July 30, 2015
    Inventors: Kevin MATOCHA, John NOWAK, Kiran CHATTY, Sujit BANERJEE
  • Patent number: 9087713
    Abstract: A semiconductor device having a JFET and diode, includes a substrate, a second well region, and a second doped region that are of a first conductivity type. The JFET also includes a first well region, a first doped region, and a shared region that are of the second conductivity type. The second well region is disposed in the substrate adjacent to the first well region. A source of the JFET includes the first doped region disposed in the first well region. An anode of the diode includes the second doped region disposed in the second well region. Both a drain of the JFET and a cathode of the diode include the shared region disposed in the first well region. A diode current flows along a first lateral axis of the device while a JFET current flows along a second lateral axis of the device.
    Type: Grant
    Filed: October 12, 2012
    Date of Patent: July 21, 2015
    Assignee: Power Integrations, Inc.
    Inventor: Sujit Banerjee
  • Publication number: 20150144573
    Abstract: A method of treating a suspension of particles in a fluid including the steps of promoting flocculation of the particles, and dewatering the flocs to form a cake with a solids content, an improvement including the step of exposing the suspension to chemicals of the protein family. The suspension can include a suspension of biological sludge in water. The suspension can be a suspension of non biological material.
    Type: Application
    Filed: July 14, 2013
    Publication date: May 28, 2015
    Inventor: Sujit Banerjee
  • Publication number: 20150084066
    Abstract: A SiC MOSFET device having low specific on resistance is described. The device has N+, P-well and JFET regions extended in one direction (Y-direction) and P+ and source contacts extended in an orthogonal direction (X-direction). The polysilicon gate of the device covers the JFET region and is terminated over the P-well region to minimize electric field at the polysilicon gate edge. In use, current flows vertically from the drain contact at the bottom of the structure into the JFET region and then laterally in the X direction through the accumulation region and through the MOSFET channels into the adjacent N+ region. The current flowing out of the channel then flows along the N+ region in the Y-direction and is collected by the source contacts and the final metal. Methods of making the device are also described.
    Type: Application
    Filed: August 11, 2014
    Publication date: March 26, 2015
    Inventors: Sujit BANERJEE, Kevin MATOCHA, Kiran CHATTY
  • Publication number: 20150014770
    Abstract: A method for fabricating a high-voltage field-effect transistor includes forming a body region, a source region, and a drain region in a semiconductor substrate. The drain region is separated from the source region by the body region. Forming the drain region includes forming an oxide layer on a surface of the semiconductor substrate over the drain region and performing a plurality of ion implantation operations through the oxide layer while tilting the semiconductor substrate such that ion beams impinge on the oxide layer at an angle that is offset from perpendicular. The plurality of ion implantation operations form a corresponding plurality of separate implanted layers within the drain region. Each of the implanted layers is formed at a different depth within the drain region.
    Type: Application
    Filed: July 12, 2013
    Publication date: January 15, 2015
    Inventors: Vijay PARTHASARATHY, Sujit BANERJEE
  • Publication number: 20140367771
    Abstract: Metal-oxide-semiconductor field-effect transistor (MOSFET) devices are described which have a p-type region between the p-type well regions of the device. The p-type region can be either floating or connected to the p-type well regions by additional p-type regions. MOSFET devices are also described which have one or more p-type regions connecting the p-type well regions of the device. The p-type well regions can be arranged in a various geometric arrangements including square, diamond and hexagonal. Methods of making the devices are also described.
    Type: Application
    Filed: June 12, 2014
    Publication date: December 18, 2014
    Inventors: Kiran CHATTY, Kevin MATOCHA, Sujit BANERJEE, Larry Burton ROWLAND
  • Patent number: 8866201
    Abstract: A high-voltage device structure comprises a resistor coupled to a tap transistor that includes a JFET in a configuration wherein a voltage provided at a terminal of the JFET is substantially proportional to an external voltage when the external voltage is less than a pinch-off voltage of the JFET. The voltage provided at the terminal being substantially constant when the external voltage is greater than the pinch-off voltage. One end of the resistor is substantially at the external voltage when the external voltage is greater than the pinch-off voltage. When the external voltage is negative, the resistor limits current injected into the substrate. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure.
    Type: Grant
    Filed: February 10, 2012
    Date of Patent: October 21, 2014
    Assignee: Power Integrations, Inc.
    Inventors: Sujit Banerjee, Vijay Parthasarathy
  • Patent number: 8823093
    Abstract: In one embodiment, a high voltage field-effect transistor (HVFET) includes a field oxide layer that covers a first well region, the field oxide layer having a first thickness and extending in a second lateral direction from a drain region to near a second well region. A gate oxide covers a channel region and has a second dimension in a first lateral direction. A gate extends in the second lateral direction from the source region to over a portion of the field oxide layer, the gate being insulated from the channel region by the gate oxide, the gate extending in the first lateral dimension over an inactive area of the HVFET beyond the second dimension of the gate oxide, the gate being insulated from the first and second well regions over the inactive area by the field oxide layer.
    Type: Grant
    Filed: June 25, 2012
    Date of Patent: September 2, 2014
    Assignee: Power Integrations, Inc.
    Inventors: Sujit Banerjee, Vijay Parthasarathy
  • Patent number: 8816433
    Abstract: In one embodiment, a transistor fabricated on a semiconductor die includes a first section of transistor segments disposed in a first area of the semiconductor die, and a second section of transistor segments disposed in a second area of the semiconductor die adjacent the first area. Each of the transistor segments in the first and second sections includes a pillar of a semiconductor material that extends in a vertical direction. First and second dielectric regions are disposed on opposite sides of the pillar. First and second field plates are respectively disposed in the first and second dielectric regions. Outer field plates of transistor segments adjoining first and second sections are either separated or partially merged.
    Type: Grant
    Filed: March 28, 2013
    Date of Patent: August 26, 2014
    Assignee: Power Integrations, Inc.
    Inventors: Vijay Parthasarathy, Sujit Banerjee, Martin H. Manley
  • Publication number: 20140187019
    Abstract: A process for fabricating a tapered field plate dielectric for high-voltage semiconductor devices is disclosed. The process may include depositing a thin layer of oxide, depositing a polysilicon hard mask, depositing a resist layer and etching a trench area, performing deep silicon trench etch, and stripping the resist layer. The process may further include repeated steps of depositing a layer of oxide and anisotropic etching of the oxide to form a tapered wall within the trench. The process may further include depositing poly and performing further processing to form the semiconductor device.
    Type: Application
    Filed: February 19, 2014
    Publication date: July 3, 2014
    Applicant: POWER INTEGRATIONS, INC.
    Inventors: Vijay PARTHASARATHY, Sujit BANERJEE, Wayne B. GRABOWSKI
  • Patent number: 8765609
    Abstract: A process for fabricating a tapered field plate dielectric for high-voltage semiconductor devices is disclosed. The process may include depositing a thin layer of oxide, depositing a polysilicon hard mask, depositing a resist layer and etching a trench area, performing deep silicon trench etch, and stripping the resist layer. The process may further include repeated steps of depositing a layer of oxide and anisotropic etching of the oxide to form a tapered wall within the trench. The process may further include depositing poly and performing further processing to form the semiconductor device.
    Type: Grant
    Filed: July 25, 2012
    Date of Patent: July 1, 2014
    Assignee: Power Integrations, Inc.
    Inventors: Vijay Parthasarathy, Sujit Banerjee, Wayne B. Grabowski
  • Patent number: 8755241
    Abstract: A method for programming a programmable block of a power IC device includes selecting an anti-fuse element of the programmable block to be programmed. The anti-fuse element includes first and second capacitive plates separated by a dielectric layer. A voltage pulse is then applied to a pin of the power IC device. The pin is connected to a drain of a high-voltage field-effect transistor (HVFET) that drives an external load via the pin during a normal operating mode of the power IC device. The voltage pulse, which is coupled to the first capacitive plate of the anti-fuse element, has a potential sufficiently high to cause a current to flow through the anti-fuse element that destroys at least a portion of the dielectric layer, thereby electrically shorting the first and second capacitive plates.
    Type: Grant
    Filed: October 19, 2012
    Date of Patent: June 17, 2014
    Assignee: Power Integrations, Inc.
    Inventors: Sujit Banerjee, Giao Minh Pham
  • Patent number: 8742495
    Abstract: In one embodiment, a vertical HVFET includes a pillar of semiconductor material a pillar of semiconductor material arranged in a loop layout having at least two substantially parallel and substantially linear fillet sections each having a first width, and at least two rounded sections, the rounded sections having a second width narrower than the first width, a source region of a first conductivity type being disposed at or near a top surface of the pillar, and a body region of a second conductivity type being disposed in the pillar beneath the source region. First and second dielectric regions are respectively disposed on opposite sides of the pillar, the first dielectric region being laterally surrounded by the pillar, and the second dielectric region laterally surrounding the pillar. First and second field plates are respectively disposed in the first and second dielectric regions.
    Type: Grant
    Filed: March 11, 2013
    Date of Patent: June 3, 2014
    Assignee: Power Integrations, Inc.
    Inventors: Vijay Parthasarathy, Sujit Banerjee, Lin Zhu
  • Publication number: 20140104888
    Abstract: A semiconductor device having a JFET and diode, includes a substrate, a second well region, and a second doped region that are of a first conductivity type. The JFET also includes a first well region, a first doped region, and a shared region that are of the second conductivity type. The second well region is disposed in the substrate adjacent to the first well region. A source of the JFET includes the first doped region disposed in the first well region. An anode of the diode includes the second doped region disposed in the second well region. Both a drain of the JFET and a cathode of the diode include the shared region disposed in the first well region. A diode current flows along a first lateral axis of the device while a JFET current flows along a second lateral axis of the device.
    Type: Application
    Filed: October 12, 2012
    Publication date: April 17, 2014
    Applicant: POWER INTEGRATIONS, INC.
    Inventor: Sujit Banerjee
  • Patent number: 8653583
    Abstract: In one embodiment, a semiconductor device includes a main vertical field-effect transistor (FET) and a sensing FET. The main vertical FET and the sense FET are both formed on a pillar of semiconductor material. Both share an extended drain region formed in the pillar above the substrate, and first and second gate members formed in a dielectric on opposite sides of the pillar. The source regions of the main vertical FET and the sensing FET are separated and electrically isolated in a first lateral direction. In operation, the sensing FET samples a small portion of a current that flows in the main vertical FET. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure.
    Type: Grant
    Filed: February 16, 2007
    Date of Patent: February 18, 2014
    Assignee: Power Integrations, Inc.
    Inventors: Vijay Parthasarathy, Sujit Banerjee, Martin H. Manley
  • Publication number: 20140030868
    Abstract: A process for fabricating a tapered field plate dielectric for high-voltage semiconductor devices is disclosed. The process may include depositing a thin layer of oxide, depositing a polysilicon hard mask, depositing a resist layer and etching a trench area, performing deep silicon trench etch, and stripping the resist layer. The process may further include repeated steps of depositing a layer of oxide and anisotropic etching of the oxide to form a tapered wall within the trench. The process may further include depositing poly and performing further processing to form the semiconductor device.
    Type: Application
    Filed: July 25, 2012
    Publication date: January 30, 2014
    Applicant: Power Integrations, Inc.
    Inventors: Vijay Parthasarathy, Sujit Banerjee, Wayne B. Grabowski
  • Publication number: 20130328114
    Abstract: A semiconductor device includes an N type well region in a P type substrate. A source region of a MOSFET is laterally separated from a boundary of the well region, which includes the drain of the MOSFET. An insulated gate of the MOSFET extends laterally from the source region to at least just past the boundary of the well region. A polysilicon layer, which forms a first plate of a capacitive anti-fuse, is insulated from an area of the well region, which forms the second plate of the anti-fuse. The anti-fuse is programmed by application of a voltage across the first and second capacitive plates sufficient to destroy at least a portion of the second dielectric layer, thereby electrically shorting the polysilicon layer to the drain of the HVFET.
    Type: Application
    Filed: August 15, 2013
    Publication date: December 12, 2013
    Applicant: Power Integrations, Inc.
    Inventors: Sujit Banerjee, Martin H. Manley
  • Publication number: 20130293256
    Abstract: A semiconductor device comprises an N type well region in a P type substrate. A source region of a MOSFET is laterally separated from a boundary of the well region, which comprises the drain of the MOSFET. An insulated gate of the MOSFET extends laterally from the source region to at least just past the boundary of the well region. A polysilicon layer, which forms a first plate of a capacitive anti-fuse, is insulated from an area of the well region, which forms the second plate of the anti-fuse. The anti-fuse is programmed by application of a voltage across the first and second capacitive plates sufficient to destroy at least a portion of the second dielectric layer, thereby electrically shorting the polysilicon layer to the drain of the HVFET. This abstract is provided to allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure.
    Type: Application
    Filed: July 2, 2013
    Publication date: November 7, 2013
    Inventors: Sujit Banerjee, Giao Minh Pham
  • Publication number: 20130234243
    Abstract: In one embodiment, a transistor fabricated on a semiconductor die is arranged into sections of elongated transistor segments. The sections are arranged in rows and columns substantially across the semiconductor die. Adjacent sections in a row or a column are oriented such that the length of the transistor segments in a first one of the adjacent sections extends in a first direction, and the length of the transistor segments in a second one of the adjacent sections extends in a second direction, the first direction being substantially orthogonal to the second direction. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure.
    Type: Application
    Filed: March 28, 2013
    Publication date: September 12, 2013
    Applicant: Power Integrations, Inc.
    Inventors: Vijay Parthasarathy, Sujit Banerjee, Martin H. Manley
  • Patent number: 8513719
    Abstract: A semiconductor device includes an N type well region in a P type substrate. A source region of a MOSFET is laterally separated from a boundary of the well region, which includes the drain of the MOSFET. An insulated gate of the MOSFET extends laterally from the source region to at least just past the boundary of the well region. A polysilicon layer, which forms a first plate of a capacitive anti-fuse, is insulated from an area of the well region, which forms the second plate of the anti-fuse. The anti-fuse is programmed by application of a voltage across the first and second capacitive plates sufficient to destroy at least a portion of the second dielectric layer, thereby electrically shorting the polysilicon layer to the drain of the HVFET.
    Type: Grant
    Filed: April 23, 2012
    Date of Patent: August 20, 2013
    Assignee: Power Integrations, Inc.
    Inventors: Sujit Banerjee, Martin H. Manley