Fast response CdS-CdSxTe1-x-CdTe core-shell nanobelt photodetector

Mingwei Tang; Pengfei Xu; Zhong Wen; Xing Chen; Chenlei Pang; Xuechu Xu; Chao Meng; Xiaowei Liu; He Tian; Nagarajan Raghavan; Qing Yang

doi:10.1016/j.scib.2018.08.003

Fast response CdS-CdS_xTe_1-_x-CdTe core-shell nanobelt photodetector

Sci Bull (Beijing). 2018 Sep 15;63(17):1118-1124. doi: 10.1016/j.scib.2018.08.003. Epub 2018 Aug 4.

Authors

Mingwei Tang¹, Pengfei Xu², Zhong Wen¹, Xing Chen³, Chenlei Pang¹, Xuechu Xu¹, Chao Meng¹, Xiaowei Liu¹, He Tian³, Nagarajan Raghavan⁴, Qing Yang⁵

Affiliations

¹ State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
² The Fifth Research Institute of Ministry of Industry and Information Technology (MIIT), Guangzhou 510610, China.
³ Center of Electron Microscopy, Zhejiang University, Hangzhou 310027, China.
⁴ Engineering Product Development (EPD) Pillar, Singapore University of Technology and Design, Singapore 487372, Singapore.
⁵ State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China; Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China. Electronic address: qingyang@zju.edu.cn.

PMID: 36658991
DOI: 10.1016/j.scib.2018.08.003

Abstract

Quasi-one-dimensional semiconductor nanostructure-based photodetectors show high sensitivity but suffer from slow response speed due to surface reaction. Here, we report a fast-response CdS-CdS_xTe_1-_x-CdTe core-shell nanobelt photodetector with a rise time of 11 μs, which is the fastest among CdS based photodetectors reported previously. The improved response speed is ascribed to the suppressed possibilities of surface reaction resulting from the core-shell structure and heterojunction among the CdS, CdS_xTe_1-_x and CdTe. The measured response spectrum of CdS-CdS_xTe_1-_x-CdTe core-shell nanobelt photodetector covers a wide range from 355 to 785 nm. Moreover, high responsivity (1,520 A/W) and large 3 dB bandwidth (∼22.9 kHz) are obtained along with the fast response. The high performance in responsivity, sensitivity, spectral response and photoresponse speed makes this device a promising candidate for practical application in optical sensing, communication and imaging.

Keywords: CdS-CdS(x)Te(1−)(x)-CdTe; Core-shell; Fast response; Photodetector.