摘要
研究了ｎ－Ｇａ１－ｘＡｌｘＡｓ（ｘ＞０．４５）的电子喇曼散射．根据晶格动力论，讨论了Ⅲ－Ⅴ合金半导体的ＤＸ中心的物理起因．结果表明在ｎ－Ｇａ１－ｘＡｌｘＡｓ（ｘ＞０．２２）中存在施主双稳态特性．在低温下，光感应的施主亚稳态是平常的类氢能级，此浅施主态引起了间接带隙ｎ－Ｇａ１－ｘＡｌｘＡｓ（ｘ＞０．４５）的电子喇曼散射和束缚声子以及直接带隙ｎ－Ｇａ１－ｘＡｌｘＡｓ（ｘ＜０．４５）的低温持续光电导．当温度升高时，该类氢能级的电子退回到稳定的ＤＸ中心的深能态．
The electronic Raman scattering in n Ga 1 x Al x As( x >0.45) is studied. According to the dynamical theory of crystal lattices, the physical origin for DX centers in Ⅲ Ⅴ alloy semiconductors is discussed.The results show that there exists a shallow deep bistable character of donors in n Ga 1-x Al x As( x >0.22). At low temperatures, the optical induced metastable state of donors is the usual hydrogen like level,which leads to the electronic Raman scattering and bound phonons in n Ga 1-x Al x As( x >0.45)of indirect band gap as well as the persistent photoconductivity in n Ga 1 x Al x As(x<0.45) of direct band gap. At higher temperatures, this hydrogen like level is depopulated to the benefit of a stable DX like deep state.
出处
《厦门大学学报（自然科学版）》
CAS
CSCD
北大核心
1999年第1期40-45,共6页
Journal of Xiamen University：Natural Science
关键词
DX中心
电子喇曼散射
低温
半导体
N型
DX centers,Electronic Raman scattering, Persistent photoconductivity
