GaN materials were etched using a CF4-based neutral beam, and its etch damage characteristics were compared with those etched with a CF4-based inductively coupled plasma (ICP). Photoluminescence data showed that the neutral beam etched GaN materials show fewer defects on the surface compared to the GaN materials etched by ICP. Also, the current-voltage characteristics of GaN light emitting diodes fabricated with p-GaN etched by the neutral beam showed less damage compared to those fabricated with p-GaN by the ICP When a photonic crystal-like structure having 2-mu m-diameter microlens array was formed using the neutral beam etching on the p-GaN of the GaN device, an increase of 20% in the optical emission intensity could be observed without significantly increasing the forward voltage (0.7). (c) 2007 American Vacuum Society.