FORMING SEMICONDUCTOR STRUCTURES INCLUDING ACTICATED ACCEPTORS IN BURIED P-TYPE GAN LAYERS

摘要

To allow hydrogen to out-diffuse from a buried Group III-nitride compound semiconductor p-type layer, the wafer is etched to form trenches in the p-type layer to expose sides of the p-type layer. After the etch, the wafer is then annealed. The duration and temperature of the anneal depend upon the spacing of the exposed sides of the p-type layer and the thickness of the p-type layer. The hydrogen diffuses easily through the p-type layer and out the sides exposed by the trenches. The result is a buried p-type layer that is more highly conductive than had the trenches not been formed prior to the anneal. In another embodiment, a surface of an acceptor-doped Group III-V p-type layer is covered with an overlying n-type layer. A portion of the n-type layer is etched to expose the surface of the p-type layer. An anneal is then carried out to out-diffuse hydrogen from the exposed surface of the p-type layer to increase the conductivity of the p-type layer.