The potential of the wide band gap semiconductor GaN and related materials for the realization of novel optoelectronic devices has been well documented [1~3]. However,the inertness of III-nitrides to the majority of conventional wet etchants was a hindrance to overcome for fabrication of devices by chemical etching. The chemical inertness of GaN resulted in either virtually no reaction with etchants or slow etch rate on the order of tens of angstroms per minute. Therefore,efficient ways of etching GaN have been sought. Recently,we found slow highly char The potential of the wide band gap GaN GaN and related materials for the realization of novel optoelectronic devices has been well documented [1-3]. However, the inertness of III-nitrides to the majority of conventional wet etchants was a hindrance to overcome for The chemical inertness of GaN by in either virtually no reaction with etchants or slow etch rate on the order of tens of angstroms per minute. Therefore, efficient ways of etching GaN have been sought. highly char