Band Alignment for Rectification and Tunneling Effects in Al2O3 Atomic-Layer-Deposited on Back Contact for CdTe Solar Cell

Yantao Su; Chao Xin; Yancong Feng; Qinxian Lin; Xinwei Wang; Jun Liang; Jiaxin Zheng; Yuan Lin; Feng Pan

doi:10.1021/acsami.6b07421

Band Alignment for Rectification and Tunneling Effects in Al₂O₃ Atomic-Layer-Deposited on Back Contact for CdTe Solar Cell

ACS Appl Mater Interfaces. 2016 Oct 19;8(41):28143-28148. doi: 10.1021/acsami.6b07421. Epub 2016 Oct 11.

Authors

Yantao Su¹, Chao Xin¹, Yancong Feng¹, Qinxian Lin¹, Xinwei Wang¹, Jun Liang¹, Jiaxin Zheng¹, Yuan Lin¹, Feng Pan¹

Affiliation

¹ School of Advanced Materials, Peking University, Peking University Shenzhen Graduate School , Shenzhen 518055, China.

PMID: 27661765
DOI: 10.1021/acsami.6b07421

Abstract

The present work intends to explain why ultrathin Al₂O₃ atomic-layer-deposited (ALD) on the back contact with rectification and tunneling effects can significantly improve the performance of CdTe solar cells in our previous work [ Liang , J. ; et al. Appl. Phys. Lett. 2015 , 107 , 013907 ]. Herein, we further study the mechanism through establishing the interfacial energy band diagram configuration of the ALD Al₂O₃/Cu_xTe by experiment of X-ray photoelectron spectroscopy and first-principles calculations and conclude to find the band alignment with optimized layer thickness (about 1 nm ALD Al₂O₃) as the key factor for rectification and tunneling effects.

Keywords: Al2O3; CdTe solar cell; atomic layer deposition; back contact; band alignment.