Electrodeless wet etching of GaN assisted with chopped ultraviolet light

Electrodeless wet etching of GaN assisted with chopped ultraviolet light

2004/5 Z.H. Hwang, J.M. Hwang, H.L. Hwang and W.H. Hung

Electrodeless photoelectrochemical (PEC) etching of GaN was studied in a K2S2O8 /KOH solution irradiated with ultraviolet (UV) light either continuously or periodically. The rate of recombination of electrons and holes at dislocation defects is greater than for crystalline GaN, resulting in a rough etched surface with hexagonal pyramids. The shorter the interval of UV irradiation, the smoother is the etched GaN surface; a chopped UV source thus serves to improve the morphology of the etched surface. A uniform and smooth GaN surface was obtained with a root-mean-square roughness 0.37 nm through electrodeless PEC etching in a solution (KOH 0.01 M, K2S2O8 0.05 M) with a chopper frequency 2500 Hz ~i.e., duration of irradiation 0.2 ms).

•  Link:

http://ieeexplore.ieee.org/xpl/abstractAuthors.jsp?arnumber=4872737

• International Journals (國際期刊):

Z.H. Hwang, J.M. Hwang, H.L. Hwang and W.H. Hung, (2004/5), Electrodeless wet etching of GaN assisted with chopped ultraviolet light, Appl. Phys. Lett. 84, 3759, [SCI], NSC 91-2215-E-007-020.

• download:

https://drive.google.com/file/d/0B-Jg2ZDReoWuT3ROZm42OFVCQ00/view?usp=sharing