Double injection in semiconductors

Abstract

A new model for double injection in high-resistivity semiconductors, containing recombination centers, is proposed. The negative resistance is associated with the presence of a saturated trap region near the minority-carrier injecting contact, which extends toward the opposite contact for increasing current. By using the regional approximation method, an analytical current-voltage characteristic is obtained which describes both the prebreakdown and negative-resistance regime. The present theory shows that the deviation from the quadratic J-vs-V behavior in the prebreakdown regime depends upon the interelectrode separation and gives a good fit for the prebreakdown characteristic of Au-GaP diodes. The theoretical breakdown voltage decreases with increasing thermal free-carrier concentration, and good quantitative agreement is found for the experimental results for GaP and InSb double-injection diodes.