Fabrication of p-Type ZnO:N Films by Oxidizing Zn₃N₂ Films in Oxygen Plasma at Low Temperature

Yuping Jin; Nuannuan Zhang; Bin Zhang

doi:10.3390/ma10030236

Fabrication of p-Type ZnO:N Films by Oxidizing Zn₃N₂ Films in Oxygen Plasma at Low Temperature

Materials (Basel). 2017 Feb 27;10(3):236. doi: 10.3390/ma10030236.

Authors

Yuping Jin¹, Nuannuan Zhang², Bin Zhang³

Affiliations

¹ Institute of Modern Physics, Fudan University, Shanghai 200433, China. ypjin15@fudan.edu.cn.
² Institute of Modern Physics, Fudan University, Shanghai 200433, China. 15210200004@fudan.edu.cn.
³ Institute of Modern Physics, Fudan University, Shanghai 200433, China. binzhang@fudan.edu.cn.

Abstract

The oxygen vacancy (V_O) is known as the main compensation center in p-type ZnO, which leads to the difficulty of fabricating high-quality p-type ZnO. To reduce the oxygen vacancies, we oxidized Zn₃N₂ films in oxygen plasma and successfully prepared p-type ZnO:N films at temperatures ranging from room temperature to 300 °C. The films were characterized by X-ray diffraction (XRD), non-Rutherford backscattering (non-RBS) spectroscopy, X-ray photoelectron spectroscopy, photoluminescence spectrum, and Hall Effect. The results show that the nitrogen atoms successfully substitute the oxygen sites in the ZnO:N films. The film prepared at room temperature exhibits the highest hole concentration of 6.22 × 10¹⁸ cm^-3, and the lowest resistivity of 39.47 Ω∙cm. In all ZnO:N films, the V_O defects are reduced significantly. At 200 °C, the film holds the lowest value of V_O defects and the strongest UV emission. These results imply that oxygen plasma is very efficient in reducing V_O defects in p-type ZnO:N films, and could greatly reduce the reaction temperature. This method is significant for the development of ZnO-based optoelectronic devices.

Keywords: oxygen plasma; oxygen vacancy (VO); p-type ZnO:N films; zinc nitrite (Zn3N2).