High quality GaN grown from a nanoporous GaN template

Abstract

High density porous GaN has been fabricated by UV-enhanced electrochemical etching on Si-doped GaN layer grown by metallorganic chemical vapor deposition. A redshift from 0.7 to 567.7 cm-1 in the E2 (high) phonon peak of GaN was observed in this porous GaN with respect to as-grown GaN. As the phonon peak of a stress-free GaN is observed at 567.5 cm-1, it means that the fabricated porous GaN is almost stress free. GaN overgrown on this porous template showed nearly doubled photoluminescence intensity as compared to that overgrown on as-grown GaN, with average surface roughness which differs only by 0.04 nm for the same thickness. This method is simple and inexpensive even for large area porous GaN fabrication and is useful for template of GaN and its alloys growth. © 2007 The Electrochemical Society.