Strain enhancement for a MoS2-on-GaN photodetector with an Al2O3 stress liner grown by atomic layer deposition  

作　　者：ZHIWEN LI JIANGLIU LUO SHENGQUN HU QIANG LIU WENJIE Yu YOUMING LU XINKE LIU 

机构地区：[1]College of Materials Science and Engineering,Shenzhen University,Shenzhen 518060,China [2]State Key Laboratory of Functional Materials for Informatics,Shanghai Institute of Microsystem and Information Technology,Chinese Academy of Sciences,Shanghai 200050,China

出　　处：《Photonics Research》2020年第6期799-805,共7页光子学研究（英文版）

基　　金：National Key Research and Development Program of China(2017YFB0403000);National Natural Science Foundation of China(61974144);Guangdong Province Key Research and Development Plan(2019B010138002);Key Research and Development Program of Guangdong Province(2020B010174003).

摘　　要：Strain regulation as an effective way to enhance the photoelectric properties of two dimensional(2D)transition metal dichalcogenides has been widely employed to improve the performance of photovoltaic devices.In this work,tensile strain was introduced in multilayer MoS2 grown on GaN by depositing 3 nm of Al2O3 on the surface.The temperature dependent Raman spectrum shows that the thermal stability of MoS2 is improved by Al2O3.Theoretical simulations confirmed the existence of tensile strain on MoS2 covered with Al2O3,and the bandgap and electron effective mass of six layers of MoS2 decreased due to tensile strain,which resulted in an increase of electron mobility.Due to the tensile strain ffect,the photodetector with the Al2O3 stress liner achieved better performance under the illumination of 365 nm wavelength,including a higher responsivity of 24.6 A/W,photoconductive gain of 520,and external quantum fficiency of 8381%,which are more than twice the corresponding values of photodetectors without Al2O3.Our work provides an effective technical way for improving the performance of 2D material photodetectors.

关 键 词：STRESS ILLUMINATION layer 

分 类 号：TB383.1[一般工业技术—材料科学与工程] TN15[电子电信—物理电子学]