Photonics Research, 2020, 8 (6): 06000799, Published Online: Apr. 30, 2020
Strain enhancement for a MoS2-on-GaN photodetector with an Al2O3 stress liner grown by atomic layer deposition Download: 817次
Abstract
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 grown on GaN by depositing 3 nm of on the surface. The temperature-dependent Raman spectrum shows that the thermal stability of is improved by . Theoretical simulations confirmed the existence of tensile strain on covered with , and the bandgap and electron effective mass of six layers of decreased due to tensile strain, which resulted in an increase of electron mobility. Due to the tensile strain effect, the photodetector with the 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 efficiency of 8381%, which are more than twice the corresponding values of photodetectors without . Our work provides an effective technical way for improving the performance of 2D material photodetectors.
Zhiwen Li, Jiangliu Luo, Shengqun Hu, Qiang Liu, Wenjie Yu, Youming Lu, Xinke Liu. Strain enhancement for a MoS2-on-GaN photodetector with an Al2O3 stress liner grown by atomic layer deposition[J]. Photonics Research, 2020, 8(6): 06000799.