The Phase Evolution and Physical Properties of Binary Copper Oxide Thin Films Prepared by Reactive Magnetron Sputtering

Weifeng Zheng; Yue Chen; Xihong Peng; Kehua Zhong; Yingbin Lin; Zhigao Huang

doi:10.3390/ma11071253

The Phase Evolution and Physical Properties of Binary Copper Oxide Thin Films Prepared by Reactive Magnetron Sputtering

Materials (Basel). 2018 Jul 20;11(7):1253. doi: 10.3390/ma11071253.

Authors

Weifeng Zheng^{1

2}, Yue Chen^{3

4}, Xihong Peng^{5

6}, Kehua Zhong^{7

8}, Yingbin Lin^{9

10}, Zhigao Huang^{11

12}

Affiliations

¹ Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy, Fujian Normal University, Fuzhou 350117, China. wfzheng3@fjnu.edu.cn.
² Fujian Provincial Engineering Technical Research Centre of Solar-Energy Conversion and Stored Energy, Fuzhou 350117, China. wfzheng3@fjnu.edu.cn.
³ Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy, Fujian Normal University, Fuzhou 350117, China. 18750712629@126.com.
⁴ Fujian Provincial Engineering Technical Research Centre of Solar-Energy Conversion and Stored Energy, Fuzhou 350117, China. 18750712629@126.com.
⁵ Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy, Fujian Normal University, Fuzhou 350117, China. jessica_p@126.com.
⁶ Fujian Provincial Engineering Technical Research Centre of Solar-Energy Conversion and Stored Energy, Fuzhou 350117, China. jessica_p@126.com.
⁷ Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy, Fujian Normal University, Fuzhou 350117, China. Khzhong@fjnu.edu.cn.
⁸ Fujian Provincial Engineering Technical Research Centre of Solar-Energy Conversion and Stored Energy, Fuzhou 350117, China. Khzhong@fjnu.edu.cn.
⁹ Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy, Fujian Normal University, Fuzhou 350117, China. Yblin@fjnu.edu.cn.
¹⁰ Fujian Provincial Engineering Technical Research Centre of Solar-Energy Conversion and Stored Energy, Fuzhou 350117, China. Yblin@fjnu.edu.cn.
¹¹ Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy, Fujian Normal University, Fuzhou 350117, China. zghuang@fjnu.edu.cn.
¹² Fujian Provincial Collaborative Innovation Center for Optoelectronic, Semiconductors and Efficient Devices, Xiamen 361005, China. zghuang@fjnu.edu.cn.

Abstract

P-type binary copper oxide semiconductor films for various O₂ flow rates and total pressures (P_t) were prepared using the reactive magnetron sputtering method. Their morphologies and structures were detected by X-ray diffraction, Raman spectrometry, and SEM. A phase diagram with Cu₂O, Cu₄O₃, CuO, and their mixture was established. Moreover, based on Kelvin Probe Force Microscopy (KPFM) and conductive AFM (C-AFM), by measuring the contact potential difference (V_CPD) and the field emission property, the work function and the carrier concentration were obtained, which can be used to distinguish the different types of copper oxide states. The band gaps of the Cu₂O, Cu₄O₃, and CuO thin films were observed to be (2.51 ± 0.02) eV, (1.65 ± 0.1) eV, and (1.42 ± 0.01) eV, respectively. The resistivities of Cu₂O, Cu₄O₃, and CuO thin films are (3.7 ± 0.3) × 10³ Ω·cm, (1.1 ± 0.3) × 10³ Ω·cm, and (1.6 ± 6) × 10¹ Ω·cm, respectively. All the measured results above are consistent.

Keywords: band gap; binary copper oxide; contact potential difference; phase structure.