The Optoelectronic Properties of p-Type Cr-Deficient Cu[Cr<sub>0.95−x</sub>Mg<sub>0.05</sub>]O<sub>2</sub> Films Deposited by Reactive Magnetron Sputtering
Song-Sheng Lin,
Qian Shi,
Ming-Jiang Dai,
Kun-Lun Wang,
Sheng-Chi Chen,
Tsung-Yen Kuo,
Dian-Guang Liu,
Shu-Mei Song,
Hui Sun
Affiliations
Song-Sheng Lin
The Key Lab of Guangdong for Modern Surface Engineering Technology, National Engineering Laboratory for Modern Materials Surface Engineering Technology, Guangdong Institute of New Materials, Guangzhou 510651, China
Qian Shi
The Key Lab of Guangdong for Modern Surface Engineering Technology, National Engineering Laboratory for Modern Materials Surface Engineering Technology, Guangdong Institute of New Materials, Guangzhou 510651, China
Ming-Jiang Dai
The Key Lab of Guangdong for Modern Surface Engineering Technology, National Engineering Laboratory for Modern Materials Surface Engineering Technology, Guangdong Institute of New Materials, Guangzhou 510651, China
Kun-Lun Wang
Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, School of Space Science and Physics, Shandong University, Weihai 264209, China
Sheng-Chi Chen
Department of Materials Engineering and Center for Plasma and Thin Film Technologies, Ming Chi University of Technology, Taipei 243, Taiwan
Tsung-Yen Kuo
Institute of Materials Science and Engineering, National Taiwan University, Taipei 106, Taiwan
Dian-Guang Liu
School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China
Shu-Mei Song
Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, School of Space Science and Physics, Shandong University, Weihai 264209, China
Hui Sun
The Key Lab of Guangdong for Modern Surface Engineering Technology, National Engineering Laboratory for Modern Materials Surface Engineering Technology, Guangdong Institute of New Materials, Guangzhou 510651, China
CuCrO2 is one of the most promising p-type transparent conductive oxide (TCO) materials. Its electrical properties can be considerably improved by Mg doping. In this work, Cr-deficient CuCrO2 thin films were deposited by reactive magnetron sputtering based on 5 at.% Mg doping. The influence of Cr deficiency on the film’s optoelectronic properties was investigated. As the film’s composition varied, CuO impurity phases appeared in the film. The mixed valency of Cu+/Cu2+ led to an enhancement of the hybridization between the Cu3d and O2p orbitals, which further reduced the localization of the holes by oxygen. As a result, the carrier concentration significantly improved. However, since the impurity phase of CuO introduced more grain boundaries in Cu[Cr0.95−xMg0.05]O2, impeding the transport of the carrier and incident light in the film, the carrier mobility and the film’s transmittance reduced accordingly. In this work, the optimal optoelectronic performance is realized where the film’s composition is Cu[Cr0.78Mg0.05]O2. Its Haacke’s figure of merit is about 1.23 × 10−7 Ω−1.
