High performance self-powered photodetector based on van der Waals heterojunction

Cong Yan; Kun Yang; Hao Zhang; Yaolin Chen; Hongxia Liu

doi:10.1088/1361-6528/ad047f

High performance self-powered photodetector based on van der Waals heterojunction

Nanotechnology. 2023 Nov 3;35(3). doi: 10.1088/1361-6528/ad047f.

Authors

Cong Yan¹, Kun Yang¹, Hao Zhang¹, Yaolin Chen¹, Hongxia Liu¹

Affiliation

¹ Key Laboratory for Wide-Band Gap Semiconductor Materials and Devices of Education, The School of Microelectronics, Xidian University, Xi'an 710071, People's Republic of China.

PMID: 37852217
DOI: 10.1088/1361-6528/ad047f

Abstract

Self-powered photodetectors that do not require external power support are expected to play a key role in future photodetectors due to their low power characteristics, but achieving high responsivity remains a challenge. 2D van der Waals heterojunctions are a promising technology for high-performance self-powered photodetectors due to their excellent optical and electrical properties. Here, we fabricate a self-powered photodetector based on In₂Se₃/WSe₂/ReS₂van der Waals heterojunction self-powered photodetector. Due to the presence of ReS₂layer, photocurrent is enhanced as a result of the increase in light absorption efficiency and the effective region for generating photogenerated carriers. The built-in electric field is enhanced by a negative 'back-gate voltage' along the p-n junction vertical direction generated by the electrons in the photo-generated electrons accumulation layer. Accordingly, the optical responsivity and the photoresponse speed of this heterojunction self-powered photodetector are greatly boosted. The proposed self-powered photodetector based on the In₂Se₃/WSe₂/ReS₂heterojunction exhibits a high responsivity of 438 mA W^-1, which is 17 times higher compared to the In₂Se₃/WSe₂photodetector, a self-powered current (1.1 nA) that is an order of magnitude higher than that of the In₂Se₃/WSe₂photodetector, and a fast response time that is 250% faster. Thus the self-powered photodetector with a stronger built-in electric field and a wider depletion zone can provide a new technological support for the fabrication of high responsivity, low power consumption and high speed self-powered photodetectors based on van der Waals heterojunctions.

Keywords: built-in electric field; depletion zone; high optical performance; self-powered photodetector; van der Waals heterojunction.