Spontaneous compositional superlattice and band-gap reduction in Si-doped AlxGa1-xN epilayers -: art. no. 191905

被引：21

作者：

Gao, M ^{[1
]}

Lin, Y

Bradley, ST

Ringel, SA

Hwang, J

Schaff, WJ

Brillson, LJ

机构：

[1] Ohio State Univ, Dept Elect & Comp Engn, Columbus, OH 43210 USA

[2] Cornell Univ, Dept Elect & Comp Engn, Ithaca, NY 14853 USA

[3] Ohio State Univ, Dept Phys, Columbus, OH 43210 USA

[4] Ohio State Univ, Ctr Mat Res, Columbus, OH 43210 USA

来源：

APPLIED PHYSICS LETTERS | 2005年 / 87卷 / 19期

基金：

美国国家科学基金会;

关键词：

D O I：

10.1063/1.2126127

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Combined transmission electron microscopy (TEM), x-ray diffraction, and cathodoluminescence spectroscopy measurements of AlxGa1-xN thin films grown by molecular-beam epitaxy reveal spontaneous modulation, phase separation, and band-gap reductions that vary systematically with AlN mole fraction across the full alloy series. At low AlN mole fraction (x <= 0.5), AlGaN epilayers display pronounced phase separation. With increasing AlN mole fraction, phase separation is strongly suppressed by the formation of spontaneous modulation, which high spatial resolution TEM techniques unambiguously determine to be an atomic-scale compositional superlattice. Superlattice-induced reductions from band gaps expected for compositionally disordered epilayers exceed several hundred meV for the Al-rich average alloy composition. (C) 2005 American Institute of Physics.

引用

页码：1 / 3

页数：3

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