N型GaN的持续光电导  

Persistent Photoconductivity In N GaN

作　　者：汪连山[1,2] 刘祥林[1,2] 岳国珍[1,2] 王晓晖[1,2] 汪度[1,2] 陆大成[1,2] 王占国[1,2] 

机构地区：[1]中国科学院半导体研究所材料科学实验室 [2]中国科学院半导体研究所表面物理实验室

出　　处：《Journal of Semiconductors》1999年第5期371-377,共7页半导体学报（英文版）

基　　金：国家"863"高技术计划

摘　　要：本文报道了金属有机物化学气相外延（ＭＯＶＰＥ）生长的未人为掺杂和掺Ｓｉｎ－ＧａＮ的持续光电导（ＰｅｒｓｉｓｔｅｎｔＰｈｏｔｏｃｏｎｄｕｃｔｉｖｉｔｙ——ＰＰＣ）．在不同温度下观察了光电导的产生和衰变行为．实验结果表明，未人为掺杂和掺Ｓｉｎ－ＧａＮ的持续光电导和黄光发射可能起源于深能级缺陷，这些缺陷可以是ＶＧａ空位、ＮＧａ反位或者ＶＧａ－ＳｉＧａ络合物．和未人为掺杂样品Ａ相比，样品Ｂ中因Ｓｉ的并入导致ＧａＮ中的深能级缺陷增加，提高了ＧａＮ中黄光发射，使持续光电导衰变减慢，但实验未发现黄光的加强和光电导衰变特性与两样品生长温度有明显关系．随测量温度的增加，持续光电导衰变加快，衰变曲线能用扩展指数定律进行拟合．Abstract This paper presents the persistent photoconductivity effect in unintentional doped and Si doped n GaN grown by metalorganic vapour phase epitaxy(MOVPE). We have observed the photoconductivity build up and its decay behavior at different temperatures. Experimental results establish that the persistent photoconductivity and yellow luminescence for unintentional doped and Si doped n GaN may originate from the deep defects associated with Ga vacancy(V Ga ), N antisite (N Ga ) or Ga vacancy complex(V Ga Si Ga ) induced by dopants. Compared to the unintentional doped sample A, the introduction of Si dopant for sample B gives an increase of deep level defects in GaN films, and strengthens the yellow luminescence and makes the photoconductivity decay slower. However, we have not observed the obvious evidence of which the yellow luminescence enhancement and photoconductivity decay characteristics are related with the growth temperature for both samples. With increasing the measurement temperature, the decay rate of persistent photoconductivity becomes quicker, and the decay curves can be well fitted by an extended exponential law.

关 键 词：氮化镓 N型 持续光电导 MOVPE 

分 类 号：TN304.23[电子电信—物理电子学]