×

LIQUID CONTACTS FOR USE IN SEMICONDUCTOR DOPING PROFILE ANALYSIS

  • US 3,803,489 A
  • Filed: 01/04/1973
  • Issued: 04/09/1974
  • Est. Priority Date: 01/04/1973
  • Status: Expired due to Term
First Claim
Patent Images

1. In apparatus for analyzing semiconductor wafers comprising means for forming a diode region on the wafer, means comprising a steady dc voltage source for reverse-biasing the diode region, thereby to form a stable depletion layer, means for adjusting the reverse-bias voltage to adjust the thickness of the depletion layer, and means for directing rf current through the diode region to determine doping densities at various depths in the wafer, the improvement wherein:

  • the diode region forming means comprises a liquid electrolyte included between a solid electrode and a first surface of the wafer;

    said electrolyte being of a material that is substantially noncontaminating and nondestructive with respect to the semiconductor wafer material, whereby wafer analysis may be accomplished without damaging the wafer.

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