Formation of GaN Self-Organized Nanotips by Reactive Ion Etching

Abstract
We describe a new method of forming self-organized GaN nanotips by reactive ion etching using chlorine plasma and its mechanism. Nanotips with a density of approximately 8×109 cm-2 have been formed after etching. The nanotips have diameters between 10 and 30 nm, a length of about 0.7 µm and a high aspect ratio. It is revealed that nanotip formation is attributed to a nanometer-scale mask with a high etch selectivity to GaN. The structure simulated using our formation mechanism is almost similar to the experimental nanotip structure. These results prove the validity of the formation mechanism by nanomasking effect of ionized SiO2 sputtered by Cl+ ions.