Patents by Inventor Jerome Chandra Bhat

Jerome Chandra Bhat 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: 6630689
    Abstract: In one embodiment of the present invention, a highly reflective dielectric stack is formed on the mesa wall of a flip-chip LED. The layers of the dielectric stack are selected to maximize reflection of light incident at angles ranging from −10 to 30 degrees, relative to the substrate. The dielectric stack is comprised of alternating low refractive index and high refractive index layers. In some embodiments, the LED is a III-nitride device with a p-contact containing silver, the dielectric stack layer adjacent to the mesa wall has a low refractive index compared to GaN, and the low refractive index layers are Al2O3.
    Type: Grant
    Filed: May 9, 2001
    Date of Patent: October 7, 2003
    Assignee: Lumileds Lighting, U.S. LLC
    Inventors: Jerome Chandra Bhat, Daniel Alexander Steigerwald
  • Patent number: 6547249
    Abstract: Series or parallel LED arrays are formed on a highly resistive substrate, such that both the p- and n-contacts for the array are on the same side of the array. The individual LEDs are electrically isolated from each other by trenches or by ion implantation. Interconnects deposited on the array connects the contacts of the individual LEDs in the array. In some embodiments, the LEDs are III-nitride devices formed on sapphire substrates. In one embodiment, two LEDs formed on a single substrate are connected in antiparallel to form a monolithic electrostatic discharge protection circuit. In one embodiment, multiple LEDs formed on a single substrate are connected in series . In one embodiment, multiple LEDs formed on a single substrate are connected in parallel. In some embodiments, a layer of phosphor covers a portion of the substrate on which one or more individual LEDs is formed.
    Type: Grant
    Filed: March 29, 2001
    Date of Patent: April 15, 2003
    Assignee: Lumileds Lighting U.S., LLC
    Inventors: William David Collins, III, Jerome Chandra Bhat, Daniel Alexander Steigerwald
  • Publication number: 20030025212
    Abstract: In one embodiment of the present invention, a highly reflective dielectric stack is formed on the mesa wall of a flip-chip LED. The layers of the dielectric stack are selected to maximize reflection of light incident at angles ranging from −10 to 30 degrees, relative to the substrate. The dielectric stack is comprised of alternating low refractive index and high refractive index layers. In some embodiments, the LED is a III-nitride device with a p-contact containing silver, the dielectric stack layer adjacent to the mesa wall has a low refractive index compared to GaN, and the low refractive index layers are Al2O3.
    Type: Application
    Filed: May 9, 2001
    Publication date: February 6, 2003
    Inventors: Jerome Chandra Bhat, Daniel Alexander Steigerwald
  • Publication number: 20020158314
    Abstract: The present invention relates to a buried mesa semiconductor device such as a laser diode with reduced leakage currents past the heterojunction, and to a method of forming such a device.
    Type: Application
    Filed: October 11, 2001
    Publication date: October 31, 2002
    Inventors: Jerome Chandra Bhat, Graham Michael Berry, Sean David Amos
  • Publication number: 20020139987
    Abstract: Series or parallel LED arrays are formed on a highly resistive substrate, such that both the p- and n-contacts for the array are on the same side of the array. The individual LEDs are electrically isolated from each other by trenches or by ion implantation. Interconnects deposited on the array connects the contacts of the individual LEDs in the array. In some embodiments, the LEDs are III-nitride devices formed on sapphire substrates. In one embodiment, two LEDs formed on a single substrate are connected in antiparallel to form a monolithic electrostatic discharge protection circuit. In one embodiment, multiple LEDs formed on a single substrate are connected in series . In one embodiment, multiple LEDs formed on a single substrate are connected in parallel. In some embodiments, a layer of phosphor covers a portion of the substrate on which one or more individual LEDs is formed.
    Type: Application
    Filed: March 29, 2001
    Publication date: October 3, 2002
    Inventors: William David Collins, Jerome Chandra Bhat, Daniel Alexander Steigerwald
  • Patent number: 6455878
    Abstract: In accordance with the invention, a difference in index of refraction is created at the mesa wall of a III-nitride flip chip light emitting device. The step in index of refraction reflects much of the light incident on the mesa wall back into the device where it can be usefully extracted. In some embodiments, a solder wall on the submount or a high index gel coating the light emitting device and the submount creates a sealed gap between the light emitting device and the submount. The gap is filled with a material having a low index of refraction. In other embodiments, a high index material covers the substrate of the light emitting device, and a low index material fills the gap between the submount and the light emitting device.
    Type: Grant
    Filed: May 15, 2001
    Date of Patent: September 24, 2002
    Assignee: LumiLeds Lighting U.S., LLC
    Inventors: Jerome Chandra Bhat, Michael Joseph Ludowise, Daniel Alexander Steigerwald