Patterning GaN Microstructures by Polarity-Selective Chemical Etching

• Published in: Japanese Journal of Applied Physics Vol. 42; no. Part 2, No. 12A; pp. L1405 - L1407
• Main Authors: Ng, Hock M., Parz, Wolfgang, Weimann, Nils G., Chowdhury, Aref
• Format: Journal Article
• Language: English
• Published: 01.12.2003
• ISSN: 0021-4922
• DOI: 10.1143/JJAP.42.L1405

Authors demonstrated GaN microstructures formed by polarity-selective chemical etching in KOH solution. KOH selectively etches N-polar GaN but not Ga-polar GaN. The polarity-patterned GaN was grown by plasma-assisted MBE. For intermediate etching times, hexagonal GaN pyramids were formed in the N-polar regions. With prolonged etching, the N-polar GaN can be completely removed. A 1-D array of GaN stripes and a 2-D array of hexagonal holes formed in a GaN matrix have been fabricated. Extremely smooth vertical sidewalls have been achieved along with an etch depth of up to 4 mu m. 14 refs.