Influence of precipitates on GaN epilayer quality

GaN epilayers grown on pre-nitridated (0001) sapphire substrates by metallorganic vapor phase epitaxy were investigated by wavelength dispersive X-ray spectroscopy and energy dispersive S-ray spectroscopy. Precipitates were observed to mainly consist of O impurity whose strengths were weaker than surrounding matrix. The precipitates were larger in size and distributed more sparsely and inhomogeneously in < 11-20 > directions of the epilayers grown on substrates pre-nitridated for longer periods. The larger precipitates often joined to cracks in the TEM specimens. The crack formation seems to be attributed to the compressive stress concentration at edge angles of the larger precipitates. Yellow luminescence of the epilayers was imaged by cathodoluminescence. The distribution similarity between the cathodoluminescence and the precipitates suggested that the precipitates were responsible for the yellow luminescence band. (C) 2000 Elsevier Science S.A, All rights reserved.

GaN epilayers grown on pre-nitridated (0001) sapphire substrates by metallorganic vapor phase epitaxy were investigated by wavelength dispersive X-ray spectroscopy and energy dispersive S-ray spectroscopy. Precipitates were observed to mainly consist of O impurity whose strengths were weaker than surrounding matrix. The precipitates were larger in size and distributed more sparsely and inhomogeneously in < 11-20 > directions of the epilayers grown on substrates pre-nitridated for longer periods. The larger precipitates often joined to cracks in the TEM specimens. The crack formation seems to be attributed to the compressive stress concentration at edge angles of the larger precipitates. Yellow luminescence of the epilayers was imaged by cathodoluminescence. The distribution similarity between the cathodoluminescence and the precipitates suggested that the precipitates were responsible for the yellow luminescence band. (C) 2000 Elsevier Science S.A, All rights reserved.

于2010-11-15批量导入

zhangdi于2010-11-15 17:02:26导入数据到SEMI-IR的IR

Made available in DSpace on 2010-11-15T09:02:26Z (GMT). No. of bitstreams: 1 2961.pdf: 714385 bytes, checksum: 2ac0b338dc19854791bdd69b7d6d9e5d (MD5) Previous issue date: 2000

IUMRS.; Amer Xtal Technol.; SUT Associates.; Univ Calif San Diego.; Shanghai Inst Met.

Xiamen Univ, Dept Phys, Xiamen 361005, Peoples R China; Chinese Acad Sci, Inst Semicond, Lab Semicond Mat Sci, Beijing 100083, Peoples R China

IUMRS.; Amer Xtal Technol.; SUT Associates.; Univ Calif San Diego.; Shanghai Inst Met.