Effect of <i>r</i>-plane (1-102) Sapphire Off-cut Angle on the Anisotropic Strain in Nonpolar Si-doped <i>a</i>-plane (11-20) GaN
Effect of <i>r</i>-plane (1-102) Sapphire Off-cut Angle on the Anisotropic Strain in Nonpolar Si-doped <i>a</i>-plane (11-20) GaN
- 주제(키워드) Nonpolar , a-plane GaN , Metal Organic Chemical Vapor Deposition , Off-cut angle , Strain
- 발행기관 한국물리학회
- 발행년도 2012
- 총서유형 Journal
- UCI G704-000411.2012.60.10.034
- KCI ID ART001667162
- 본문언어 영어
초록/요약
We studied the growth and the characteristics of nonpolar Si-doped a-plane GaN grown on rplane sapphire substrates with different off-cut angles which were changed in the range of −0.2˚ ∼ +0.4˚. Samples grown by using −0.2 and +0.2˚ off-cut angles showed triangular pit-free and smooth surfaces, which resulted from enhanced lateral growth owing to the epitaxial films having a Ga face. On the other hand, the sample grown by using +0.4˚ off-cut angles revealed a high density of pits and low crystalline quality due to a high density of dislocations. The strain determined by using calculations with the lattice parameters also showed a dependence on the off-cut angles. We expect r-plane sapphire with off-cut angles in the range of −0.2˚ ∼ +0.2˚ to be very ffective for improving the crystalline quality and the surface morphology of a-plane GaN.
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