Properties of N-doped P-ZnO Films Deposited Using Plasma Enhanced Atomic Layer Deposition

Abstract

Plasma enhanced atomic layer deposition (PEALD) technique was used to deposit nitrogendoped (N-doped) ZnO thin films on sapphire substrate. The nitrogen-doped ZnO thin films were deposited at various substrate temperatures from 75℃to 250℃. The plasma source was used to decompose the ammonia (NH3) gas and form N, NH and NH2 as the nitrogen dopant source. The post-annealing treatment was conducted to remove the hydrogen ions in the as-grown nitrogen-doped ZnO films at 900℃, in oxygen ambience by a rapid thermal annealing (RTA) system. The electrical and optical properties of the N-doped ZnO films were characterized by Hall measurements, low temperature photoluminescence (LTPL) spectroscopy and X-ray photoelectron spectroscopy (XPS), in order to prove the thin film was the p-type ZnO. The highest hole concentration of 4.04×10^17 cm^(-3), the lowest resistivity of 52.10 Ω-cm, and the hole mobility of 0.55 cm^2/V-s for N-doped ZnO can be obtained at substrate temperature of 100℃.