Premium
Characterization of Ar ion etching induced damage for GaN
Author(s) -
Kataoka Keita,
Kimoto Yasuji,
Horibuchi Kayo,
aka Takamasa,
Takahashi Naoko,
Narita Tetsuo,
Kanechika Masakazu,
Dohmae Kazuhiko
Publication year - 2012
Publication title -
surface and interface analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.52
H-Index - 90
eISSN - 1096-9918
pISSN - 0142-2421
DOI - 10.1002/sia.3876
Subject(s) - materials science , luminescence , dangling bond , transmission electron microscopy , etching (microfabrication) , amorphous solid , layer (electronics) , analytical chemistry (journal) , crystallinity , absorption (acoustics) , optoelectronics , chemistry , nanotechnology , crystallography , composite material , silicon , chromatography
We studied the overall picture of the etching‐induced damage for GaN films. By using Ar ion etching, we characterized the damage for GaN from various perspectives by AES, transmission electron microscopy, X‐ray absorption spectroscopy, and cathode luminescence. From AES results, it was found that N on GaN surface is selectively etched. After air exposure, the near surface layer within the damage layer was oxidized by the existence of the chemically active dangling bonds. The thickness of the damage layer was observed by cross‐sectional transmission electron microscopy as the dimmed layer, which is caused by the absence of translation symmetry, in other words, degradation of the crystallinity introduced by crystal defects and/or transformation into an amorphous phase in nanoscale. Total reflection X‐ray absorption near‐edge structure spectrum indicated the gradual change from GaN to Ga oxide with higher Ar ion acceleration voltage. Moreover, the etching‐induced nonradiative defects were detected by comparing the cathode luminescence intensities. The various phenomena of the damage can be comprehensively evaluated by using these methods, and the overall picture of etching‐induced damage for GaN was revealed. Copyright © 2011 John Wiley & Sons, Ltd.