立方相GaN的持续光电导  

Investigation on Persistent Photoconductivity Effect in Cubic GaN

作　　者：张泽洪[1] 赵德刚[1] 孙元平[1] 冯志宏[1] 沈晓明[1] 张宝顺[1] 冯淦[1] 郑新和[1] 杨辉[1] 

机构地区：[1]中国科学院半导体研究所集成光电子国家重点联合实验室,北京100083

出　　处：《Journal of Semiconductors》2003年第1期34-38,共5页半导体学报（英文版）

基　　金：国家自然科学基金 (批准号 :6982 5 10 7) ;NSFC-RGC联合基金 (Nos.5 0 0 116195 3 ;N HKU 0 2 8/ 0 0 )资助项目~~

摘　　要：研究了金属有机物化学气相外延 (MOVPE)方法生长的非故意掺杂的立方相 Ga N的持续光电导效应 .在六方相 Ga N中普遍认为持续光电导效应与黄光发射有关 ,而实验则显示在立方 Ga N中 ,持续光电导效应与其中的六方相 Ga N夹杂有关系 ,而与黄光发射没有关系 .文中提出 ,立方相 Ga N与其中的六方相 Ga N夹杂之间的势垒引起的空间载流子分离是导致持续光电导现象的物理原因 .通过建立势垒限制复合模型 ,解释了立方相 Ga N的持续光电导现象的物理过程 ,并对光电导衰减过程的动力学作了分析 .对实验数据拟合的结果证明以上的模型和推导是与实验相符的 .The persistent photoconductivity (PPC) effect in unintentional doped cubic GaN grown on GaAs(001) substrate by metalorganic chemical vapor deposition (MOCVD) is studied.It is widely accepted that the PPC effect in hexagonal GaN is related to the yellow luminescence (YL).However,we observe that in cubic GaN,it is induced by the unintentionally incorporated hexagonal crystallites in cubic matrix and has nothing to do with YL.We suggest that the spatial carrier separation caused by the barrier between the cubic matrix and hexagonal crystallites is the reason of the PPC effect.A barrier-limited model is developed to analyze the decay process,and the decay kinetics is discussed.The result of data fitting confirms our model and conclusion.

关 键 词：立方相 GAN 持续光电导 空间载流子分离 势垒限制复合 氮化镓 

分 类 号：TN304.23[电子电信—物理电子学]