一种减小GaN基肖特基结构紫外探测器暗电流的方法  

A new method to reduce the dark current of GaN based Schottky barrier ultraviolet photodetector

作　　者：周梅[1] 常清英[1] 赵德刚[2] 

机构地区：[1]中国农业大学应用物理系,北京100083 [2]中国科学院半导体研究所集成光电子学国家重点实验室,北京100083

出　　处：《物理学报》2008年第4期2548-2553,共6页Acta Physica Sinica

基　　金：中国农业大学青年教师科研启动基金(批准号:2006007)资助的课题~~

摘　　要：提出了一种减小GaN肖特基结构紫外探测器暗电流的方法.该方法是在普通的GaN肖特基结构的表面增加一层薄的p-GaN.模拟计算结果表明,该层p-GaN能增加肖特基势垒高度,从而减小了器件的暗电流,提高了器件性能.进一步的计算还发现,对于p型载流子浓度较高的情况下,只需要很薄的一层p-GaN就能显著增加肖特基势垒高度,对于p型载流子浓度较低的情况下,则需要较厚的一层p-GaN才能有较好的肖特基势垒高度增加效果.A new method to reduce the dark current of GaN based Schottky barrier ultraviolet photodetector is proposed. In comparision with conventional i-GaN/n^＋ -GaN structure, an additional thin p-GaN cap layer is introduced on the i-GaN（n^- -GaN） in the new structure. The simulation results showed that the additional layer makes the dark current to decrease in the photodetector due to the increase of the Schottky barrier height. The effects of thickness and carrier concentration of p-GaN layer on the dark current of the photodetector were also studied. It is suggested that the dark current of the new structure device could be better reduced by employing p-GaN with higher carrier concentration as the cap layer.

关 键 词：GAN 肖特基结构 紫外探测器 暗电流 

分 类 号：O472[理学—半导体物理]