PROPOSAL FOR THE FORMATION OF A MINORITY-CARRIER INJECTING CONTACT ON WIDE BANDGAP SEMICONDUCTORS

We propose a new method by which a minority carrier injection contact or ohmic contact can be attained. The basic principle is to use a forming process, i.e. an applied electric field at an elevated temperature in the Schottky contact, to spatially separate dopants from compensating centers. In this way, the ratio of dopants to the compensating centers can be greatly increased at the semiconductor surface. Upon cooling, the dopant concentrations are frozen to retain a large net concentration of dopants in a thin surface layer, resulting in a depletion layer that is sufficiently thin to allow tunneling injection.