N型合金半导体的低温电子喇曼散射  

Electronic Raman Scattering in n type Ⅲ Ⅴ Alloy Semiconductors at Low Temperatures

作　　者：连世阳[1] 

机构地区：[1]厦门大学物理学系

出　　处：《厦门大学学报（自然科学版）》1999年第1期40-45,共6页Journal of Xiamen University：Natural Science

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.

关 键 词：DX中心 电子喇曼散射 低温 半导体 N型 

分 类 号：O472.3[理学—半导体物理] O474[理学—物理]