Patent ID: 7829435

Claim:
A GaN-based element fabrication method comprising: a growing step of sequentially growing a metal buffer layer, a metal nitride layer and a single-crystal GaN layer on an underlying substrate; an element structure fabrication step of fabricating a GaN-based element structure on the GaN single-crystal layer; and a chip separation step of separating a stacking structure including the underlying substrate, the metal buffer layer, the metal nitride layer, the single-crystal GaN layer, and the GaN-based element structure, into a plurality of chips wherein the metal buffer layer and the metal nitride layer respectively include a Cu layer and a Cu nitride layer, alternatively the metal buffer layer and the metal nitride layer respectively include a chromium layer and a chromium nitride layer; and the chip separation step includes: a bonding step of bonding a conductive support substrate to the GaN-based element structure through a conductive junction; a primary scribing step of scribing the stacking structure supported by the conductive support substrate, such that the stacking structure is divided into a plurality of stacking bodies; an etching step of etching the metal buffer layer and the metal nitride layer by selective chemical etching to remove the underlying substrate from each of the stacking bodies; a secondary scribing step of scribing the conductive support substrate at spaces between the stacking bodies, such that the stacking bodies are separated into the plurality of chips.