(Invited) Applications of Electrochemistry for Novel Wide Bandgap GaN Devices

Abstract

Electrochemical (EC) etching having large selectivity based on the conductivity of n-type GaN was investigated to demonstrate the feasibility of novel wide bandgap GaN devices. The EC etching relies on the generation of holes at the GaN/electrolyte surface for oxidation and chemical dissolution. Depending on the layer conductivity and applied bias, the EC etching may cause no effect, nanoscale porosification, or complete etching of GaN. The EC etching has been applied to different areas of GaN material and device technologies, including layer separation, the preparation of flexible GaN membrane devices, and the formation of distributed Bragg reflector for photonic applications.