Patents by Inventor James A. Tatum

James A. Tatum 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: 9318639
    Abstract: An avalanche photodiode can include: an avalanche region having one or more layers prepared from GaAs; an N? absorption layer extending across the avalanche region; an N-type layer above at least a center portion of the N? absorption layer; and optionally a lower conductivity layer laterally from the N-type layer to a surface of the avalanche region and above a perimeter portion of the N? absorption layer, the lower conductivity layer having lower conductivity compared to the N-type layer. The avalanche photodiode can include a window layer above the N-type layer and lower conductivity layer, and an anode contact above the window layer. The avalanche photodiode can include an N+ barrier layer below the N? absorption layer, an N+ conduction layer below the N+ barrier layer, a substrate below the N+ conduction layer, and a cathode contact coupled with the N+ conduction layer.
    Type: Grant
    Filed: September 16, 2014
    Date of Patent: April 19, 2016
    Assignee: FINISAR CORPORATION
    Inventors: James A. Tatum, James R. Biard
  • Publication number: 20150076647
    Abstract: An avalanche photodiode can include: an avalanche region having one or more layers prepared from GaAs; an N? absorption layer extending across the avalanche region; an N-type layer above at least a center portion of the N? absorption layer; and optionally a lower conductivity layer laterally from the N-type layer to a surface of the avalanche region and above a perimeter portion of the N? absorption layer, the lower conductivity layer having lower conductivity compared to the N-type layer. The avalanche photodiode can include a window layer above the N-type layer and lower conductivity layer, and an anode contact above the window layer. The avalanche photodiode can include an N+ barrier layer below the N? absorption layer, an N+ conduction layer below the N+ barrier layer, a substrate below the N+ conduction layer, and a cathode contact coupled with the N+ conduction layer.
    Type: Application
    Filed: September 16, 2014
    Publication date: March 19, 2015
    Inventors: James A. Tatum, James R. Biard
  • Patent number: 6965626
    Abstract: A VCSEL having a metallic heat spreading layer adjacent a semiconductor buffer layer containing an insulating structure. The heat spreading layer includes an opening that enables light emitted by an active region to reflect from a distributed Bragg reflector (DBR) top mirror located above the heat spreading layer. A substrate is below the active region. A lower contact provides electrical current to that substrate. The lower contact includes an opening that enables light emitted from the active region to reflect from a distributed Bragg reflector (DBR) lower mirror. Beneficially, the substrate includes a slot that enables light to pass through an opening in the lower contact. That slot acts as an alignment structure that enables optical alignment of an external feature to the VCSEL.
    Type: Grant
    Filed: September 3, 2002
    Date of Patent: November 15, 2005
    Assignee: Finisar Corporation
    Inventors: James A. Tatum, James K Guenter, Ralph H. Johnson
  • Publication number: 20040042518
    Abstract: A VCSEL having a metallic heat spreading layer adjacent a semiconductor buffer layer containing an insulating structure. The heat spreading layer includes an opening that enables light emitted by an active region to reflect from a distributed Bragg reflector (DBR) top mirror located above the heat spreading layer. A substrate is below the active region. A lower contact provides electrical current to that substrate. The lower contact includes an opening that enables light emitted from the active region to reflect from a distributed Bragg reflector (DBR) lower mirror. Beneficially, the substrate includes a slot that enables light to pass through an opening in the lower contact. That slot acts as an alignment structure that enables optical alignment of an external feature to the VCSEL.
    Type: Application
    Filed: September 3, 2002
    Publication date: March 4, 2004
    Inventors: James A. Tatum, James K. Guenter, Ralph H. Johnson