Ga vacancies and grain boundaries in GaN

被引：25

作者：

Oila, J

Saarinen, K

Wickenden, AE

Koleske, DD

Henry, RL

Twigg, ME

机构：

[1] Aalto Univ, Phys Lab, FIN-02015 Espoo, Finland

[2] USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA

来源：

APPLIED PHYSICS LETTERS | 2003年 / 82卷 / 07期

关键词：

D O I：

10.1063/1.1542946

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We have applied a low-energy positron beam to study epitaxial Si-doped GaN layers, where the grain size varies from 0.2 to 2-5 mum. Negatively charged Ga vacancies are found in n-type samples. Their concentration is independent of the grain size, suggesting that Ga vacancies exist in the grain interior. Positrons are observed to get trapped also at other negatively charged centers. The positron trapping rate at these defects correlates with the grain-boundary density. We attribute the observed shallow positron traps, which do not contain open volume, to negatively charged edge-type dislocations which define the grain boundaries. (C) 2003 American Institute of Physics.

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收藏

页码：1021 / 1023

页数：3

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