Dry etch damage in n-type GaN and its recovery by treatment with an N-2 plasma

We report on etch-induced damage in n-type GaN caused by an inductively cou pled plasma, and damage recovery by means of treatment with an N-2 plasma. As the plasma dc bias was increased by increasing the rf table power during etching, the optical and electrical properties of the etched GaN films det eriorated as the result of etch-induced damage. However, an N-2 plasma trea tment for the etched samples effectively removed the etch-induced defects a nd damage on the surface, leading to improved surface morphology, photolumi nescence, and ohmic contact in n-type GaN. (C) 2000 American Institute of P hysics. [S0021-8979(00)05211-7].