Thickness effect on solar-blind photoelectric properties of ultrathinβ-Ga_(2)O_(3)films prepared by atomic layer deposition  

作　　者：王少青 程妮妮 王海安 贾一凡 陆芹 宁静 郝跃 刘祥泰 陈海峰 Shao-Qing Wang;Ni-Ni Cheng;Hai-An Wang;Yi-Fan Jia;Qin Lu;Jing Ning;Yue Hao;Xiang-Tai Liu;Hai-Feng Chen(The Key Laboratory of Advanced Semiconductor Devices and Materials,Xi’an University of Posts&Telecommunications,Xi’an 710121,China;The State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology,Xidian University,Xi’an,710071,China)

机构地区：[1]The Key Laboratory of Advanced Semiconductor Devices and Materials,Xi’an University of Posts&Telecommunications,Xi’an 710121,China [2]The State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology,Xidian University,Xi’an,710071,China

出　　处：《Chinese Physics B》2023年第4期707-713,共7页中国物理B（英文版）

基　　金：Project supported by the Natural Science Basic Research Program of Shaanxi Province,China(Grant No.2022JQ-701);the Scientific Research Program Funded by Shaanxi Provincial Education Department,China(Grant No.21JK0919)。

摘　　要：Theβ-Ga_(2)O_(3)films with different thicknesses are prepared by an atomic layer deposition system.The influence of film thickness on the crystal quality is obvious,indicating that the thicker films perform better crystal quality,which is verified from x-ray diffraction(XRD)and scanning electron microscope(SEM)results.The Ga_(2)O_(3)-based solar blind photodetectors with different thicknesses are fabricated and studied.The experimental results show that the responsivity of the photodetectors increases exponentially with the increase of the film thickness.The photodetectors with inter-fingered structure based on 900 growth cyclesβ-Ga_(2)O_(3)active layers(corresponding film thickness of 58 nm)exhibit the best performances including a low dark current of 134 fA,photo-to-dark current ratio of 1.5×10^(7),photoresponsivity of 1.56 A/W,detectivity of 2.77×10^(14)Jones,and external quantum efficiency of 764.49%at a bias voltage of 10 V under 254-nm DUV illumination.The photoresponse rejection ratio(R_(254)/R_(365))is up to 1.86×10^(5).In addition,we find that the photoelectric characteristics also depend on the finger spacing of the MSM structure.As the finger spacing decreases from 50μm to10μW,the photoresponsivity,detectivity,and external quantum efficiency increase significantly.

关 键 词：β-Ga_(2)O_(3) film thickness solar blind photodetectors photoelectric response 

分 类 号：TN36[电子电信—物理电子学] TQ133.51[化学工程—无机化工] TB383.2[一般工业技术—材料科学与工程]