×

IGBT device with platinum lifetime control and reduced gaw

  • US 5,528,058 A
  • Filed: 10/13/1994
  • Issued: 06/18/1996
  • Est. Priority Date: 03/21/1986
  • Status: Expired due to Term
First Claim
Patent Images

1. An improved MOS-type insulated gate controlled power switching device comprising:

  • a semiconductor substrate having a first layer of a first dopant type defining a device anode and second layer of a second, opposite-polarity dopant type defining a drain region extending from an upper surface of the substrate toward the first layer;

    an insulative layer on the upper surface of the second layer of the substrate;

    an insulated gate contact layer on the insulative layer;

    double diffused regions including a body region of the first dopant type and a source region of the second dopant type within the body region, the body region forming two PN junctions with the drain and source regions, respectively spaced apart so as to define a channel region in the body region subjacent the insulated gate contact;

    a source contact alongside the gate contact but spaced insulatively therefrom, the source contact forming an electrical connection to the source region and the body region and a short therebetween and defining a cathode contact for the device;

    an anode contact on the opposite side of the substrate in electrical connection to the first layer;

    the second layer including;

    a first portion contacting the first layer and having a first thickness and a first doping concentration extending substantially uniformly across said first thickness;

    a second portion contacting the first portion of the second layer and extending to said upper surface adjacent said double diffused regions;

    the second portion being sized to a second thickness and doped to a second doping concentration extending substantially uniformly across said second thickness sufficient to block a predetermined maximum reverse bias voltage; and

    the first portion being sized to a thickness greater than 20 micrometers and doped to a first doping concentration greater than the second doping concentration and less than 1016 atoms/cm3 to produce a predetermined output impedance (Ro) sufficient to resist current flow during forward conduction when a high voltage (Vec) is across the cathode and anode contacts.

View all claims
  • 4 Assignments
Timeline View
Assignment View
    ×
    ×