The Effect of mass transfer on the photoelectrochemical etching of GaN

摘要

Epitxial layers of gallium nitride (GaN) grown on sapphire were photoelectrochemically etched in KOH solutions of varying concentrations (0.01 -0.6 M), light intensities (60-840 mW cm~-2) and stirring speeds. Etch rates as high as 1 μm min~-1 were observed with a metal mask forming A surface consisting of 100 μm with GaN stripes spaced with 150 μm gold Stripes. A characteristic etch profile, indicative of accelerated etching near The mask edges (inverted U shape), was consistently observed when using Low concentrations of the etchant.