High-performing visible-blind photodetectors based on SnO2/CuO nanoheterojunctions

Ting Xie; Md Rezaul Hasan; Botong Qiu; Ebuka S Arinze; Nhan V Nguyen; Abhishek Motayed; Susanna M Thon; Ratan Debnath

doi:10.1063/1.4938129

High-performing visible-blind photodetectors based on SnO₂/CuO nanoheterojunctions

Appl Phys Lett. 2015 Dec;107(24):241108. doi: 10.1063/1.4938129. Epub 2015 Dec 18.

Authors

Ting Xie^{1

2}, Md Rezaul Hasan^{1

3}, Botong Qiu⁴, Ebuka S Arinze⁴, Nhan V Nguyen⁵, Abhishek Motayed¹, Susanna M Thon⁴, Ratan Debnath¹

Affiliations

¹ Materials Science and Engineering Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 USA.
² Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland 20742, USA.
³ Department of Electrical and Computer Engineering, George Mason University, 4400 University Drive, Fairfax, Virginia 22030, USA.
⁴ Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA.
⁵ Semiconductor and Dimensional Metrology Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899 USA.

Abstract

We report on the significant performance enhancement of SnO₂ thin film ultraviolet (UV) photodetectors (PDs) through incorporation of CuO/SnO₂p-n nanoscale heterojunctions. The nanoheterojunctions are self-assembled by sputtering Cu clusters that oxidize in ambient to form CuO. We attribute the performance improvements to enhanced UV absorption, demonstrated both experimentally and using optical simulations, and electron transfer facilitated by the nanoheterojunctions. The peak responsivity of the PDs at a bias of 0.2 V improved from 1.9 A/W in a SnO₂-only device to 10.3 A/W after CuO deposition. The wavelength-dependent photocurrent-to-dark current ratio was estimated to be ~ 592 for the CuO/SnO₂ PD at 290 nm. The morphology, distribution of nanoparticles, and optical properties of the CuO/SnO₂ heterostructured thin films are also investigated.

Grants and funding

9999-NIST/Intramural NIST DOC/United States