標題: | Method for modulating the wafer bow of free-standing GaN substrates via inductively coupled plasma etching |
作者: | Chen, Kuei-Ming Yeh, Yen-Hsien Wu, Yin-Hao Chiang, Chen-Hao Yang, Din-Ru Chao, Chu-Li Chi, Tung-Wei Fang, Yen-Hsang Tsay, Jenq-Dar Lee, Wei-I 電子物理學系 Department of Electrophysics |
關鍵字: | Etching;GaN substrate;Hydride vapor phase epitaxy;Nitrides;GaN |
公開日期: | 1-十二月-2010 |
摘要: | The bowing curvature of the free-standing GaN substrate significantly decreased almost linearly from 067 to 0 056 m(-1) (i e the bowing radius increased from 1 5 to 178 m) with increase in inductively coupled plasma (ICP) etching time at the N-polar face and eventually changed the bowing direction from convex to concave Furthermore the Influences of the bowing curvature on the measured full width at half maximum (FWEIM) of high-resolution X-ray diffraction (HRXRD) in (0 0 2) reflection were also deduced which reduced from 176 8 to 888 arcsec with increase in ICP etching time Decrease in the nonhomogeneous distribution of threading dislocations and point defects as well as V(Ga)-O(N) complex defects on removing the GaN layer from N-polar face which removed large amount of defects was one of the reasons that improved the bowing of the free-standing GaN substrate Another reason was the high aspect ratio of needle-like GaN that appeared at the N-polar face after ICP etching which released the compressive strain of the free-standing GaN substrate By doing so crack-free and extremely flat free-standing GaN substrates with a bowing radius of 178 m could be obtained (C) 2010 Elsevier B V All rights reserved |
URI: | http://dx.doi.org/10.1016/j.jcrysgro.2010.09.044 http://hdl.handle.net/11536/31875 |
ISSN: | 0022-0248 |
DOI: | 10.1016/j.jcrysgro.2010.09.044 |
期刊: | JOURNAL OF CRYSTAL GROWTH |
Volume: | 312 |
Issue: | 24 |
起始頁: | 3574 |
結束頁: | 3578 |
顯示於類別: | 期刊論文 |