Etching techniques for the realization of semiconductor devices based on III-V nitrides

Summary form only given. III-V nitride semiconductors have attracted a great deal of attention in the last decade, especially for optical devices such as blue laser diodes and high frequency, high power and high temperature electronic devices such as high electron mobility transistors (HEMTs). Due to the inert chemical characteristics of III-V nitrides, difficulty incurs in etching nitrides for device applications. The formation of laser cavity facets in particular must resort to well-developed etching techniques; on the other hand, low-damage etching techniques are indispensable for the fabrication of recessed-gate HEMTs. In this study, we compare three etching techniques, photo-assisted cryogenic etching, photoelectrochemical (PEC) etching and reactive ion beam etching (RIBE), and examine the feasibility of producing the vertical sidewall and low-damage etch surface for real device applications