GaN基p-i-n型雪崩探测器的制备与表征(英文)  

Fabrication and Characterization of GaN Based p-i-n Avalanche Photodetectors

作　　者：李广如[1] 秦志新[1] 桑立雯[1] 沈波[1] 张国义[1] 

机构地区：[1]北京大学物理学院人工微结构和介观物理国家重点实验室,北京100871

出　　处：《发光学报》2011年第3期262-265,共4页Chinese Journal of Luminescence

基　　金：Projects supported by National Natural Science Foundation of China Grant(10774001,60736033,60876041,60577030)~~

摘　　要：制备和表征了p-i-n型的GaN基雪崩探测器。器件在-5 V下的暗电流约为0.05 nA,-20 V下的暗电流小于0.5 nA。响应增益-偏压曲线显示,可重复的雪崩增益起始于80 V附近,在85 V左右增益达到最大为120,表明所制备的器件具有较好的质量。C-V测量用来确定载流子的分布和耗尽信息,结果显示,p型层在15 V左右达到耗尽,对应的空穴载流子浓度在1.9×1017 cm-1左右,相对低的载流子浓度降低了电场限制,使探测器的工作电压相对偏高。在不同偏压下测量的光谱响应曲线显示出明显的Franz-Keldysh效应。p-i-n GaN based avalanche UV photodetectors were fabricated and characterized.Dark current of the device is as low as 0.05 nA at the reverse bias of 5 V and 0.5 nA at 20 V.Repeatable photocurrent avalanche gain,began at around 80 V and grew up to a peak of 120 at about 85 V,demonstrating a good material quality.C-V mea-surement was used to determine carrier distribution and depletion information,and it showed that p-layer fully depleted at reverse bias of about 15 V,resulting in a hole concentration of 1.9×1017 cm-3.The relative low hole concentration might lead to a weak confinement of electrical field and an increase in the operating voltage of the device.Photocurrent spectroscopy under various bias was also measured and exhibited obvious Franz-Keldysh effect.

关 键 词：紫外探测器 雪崩 碰撞电离 

分 类 号：TN364[电子电信—物理电子学]