PROCESS FOR PRODUCING LAMINATE COMPRISING AL-BASED GROUP III NITRIDE SINGLE CRYSTAL LAYER, LAMINATE PRODUCED BY THE PROCESS, PROCESS FOR PRODUCING AL-BASED GROUP III NITRIDE SINGLE CRYSTAL SUBSTRATE USING THE LAMINATE, AND ALUMINUM NITRIDE SINGLE CRYSTAL SUBSTRATE

摘要

The present invention is a method for producing a laminated body, comprising the steps of: (1) preparing a base substrate having a surface formed of a single crystal which is different from the material constituting the Al-based group-III nitride single crystal layer to be formed; (2) forming an Al-based group-III nitride single crystal layer having a thickness of 10 nm to 1.5 µm on the single crystal surface of the prepared base substrate; (3) forming on the Al-based group-III nitride single crystal layer a non-single crystal layer being 100 times or more thicker than the Al-based group-III nitride single crystal layer without breaking the previously-obtained Al-based group-III nitride single crystal layer; and (4) removing the base substrate. The method provides a substrate which can be suitably used as a base substrate for producing an Al-based group-III nitride single crystal self-supporting substrate, of which surface is formed of a single crystal of an Al-based group-III nitride, and which is free from cracking and warpage.