Electrical Properties of Gold-Doped Diffused Silicon Computer Diodes

Abstract

Planar diffused silicon junctions with storage times of one millimicrosecond or less are readily obtained by gold doping. The introduction of uniform gold concentrations (in the range from 1.2 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">15</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−3</sup> to 8 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">16</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−3</sup> ) is conveniently done using solid state diffusion techniques. The gold diffusion technique allows relatively precise control of recombination center density, and, although applicable to almost any diffused silicon device, is particularly useful in control of storage time in small-area diffused silicon computer diodes. In this application, reverse recovery time of about one millimicrosecond may be obtained without substantial degradation of other electrical parameters. The process of gold doping by diffusion and its effect on electrical characteristics of diffused silicon computer diodes are discussed. Included are comparisons of first-order calculations and experimental results for variations of reverse recovery time, reverse current and forward current with gold atom density.