Zixuan Liao, Jidong Li, Yuyang Long, Han Sheng, Xiao Wang, Xuemei Li, Wanlin Guo, Jun Yin

ACS Applied Materials & Interfaces  , 15, 49, 57812-57817,  2023.

Abstract: Photodetectors based on semiconductor devices have been widely used to sense light position, intensity, and wavelength. However, monitoring the motion velocity of a light beam generally requires complex integration of device arrays. Here, we report a single device of a simple metal–insulator–semiconductor structure for self-powered sensing not only position but also velocity of a light beam or shadow. A velocity-dependent voltage output between two terminals of the metal is observed. It is attributed to light illumination-induced local surface potential change in semiconductors and the following movement of local charges accumulated in the metal due to capacitive coupling. The amplitude of the velocity-dependent voltage can be facilely modulated by applying a gate voltage. These results shed light on compact devices with multiple sensing functions.

Keywords: metal−insulator–semiconductor structures; position; velocity; sensor; surface photovoltage.

Link: https://pubs.acs.org/doi/full/10.1021/acsami.3c12722