Protective capping layer for spalled gallium nitride

Abstract

Described herein is a method for manufacturing a stack of semiconductor materials in which a growth substrate is separated from the stack after a semiconductor material, e.g., a Group III nitride semiconductor material, is grown on the substrate. The separation is effected in a spalling procedure in which spalling-facilitating layers are deposited over a protective cap layer that is formed over the Group III-nitride semiconductor material. Such spalling-facilitating layers may include a handle layer, a stressor layer, and an optional adhesion layer. The protective cap layer protects the Group III-nitride from being damaged by the depositing of one or more of the spalling-facilitating layers. After spalling to remove the growth substrate, additional processing steps are taken to provide a semiconductor device that includes undamaged semiconductor material. In one arrangement, the semiconductor material is GaN and includes p-doped GaN region that was undamaged during manufacturing.