Chinese Optics Letters, 2021, 19 (8): 082504, Published Online: Jul. 23, 2021
Carrier transport and photoconductive gain mechanisms of AlGaN MSM photodetectors with high Al Content Download: 622次
Abstract
We have fabricated the AlGaN solar-blind ultraviolet metal–semiconductor–metal (MSM) photodetectors (PDs) with an Al composition of 0.55. The surface roughness and dislocations of the high-Al-content epitaxial layer are analyzed by atomic force microscopy and transmission electron microscopy, respectively. The device exhibits high spectral responsivity and external quantum efficiency due to the photoconductive gain effect. The current reveals a strong dependence on high temperatures in the range of 4–10 V. Moreover, the Poole–Frenkel emission model and changing space charge regions are employed to explain the carrier transport and photoconductive gain mechanisms for the AlGaN PD, respectively.
Zhicheng Dai, Yushen Liu, Guofeng Yang, Feng Xie, Chun Zhu, Yan Gu, Naiyan Lu, Qigao Fan, Yu Ding, Yuhang Li, Yingzhou Yu, Xiumei Zhang. Carrier transport and photoconductive gain mechanisms of AlGaN MSM photodetectors with high Al Content[J]. Chinese Optics Letters, 2021, 19(8): 082504.