Abstract
The effect of nitrogen content on compensation of N-related defects in Al-N codoped Mg 0.05 Zn 0.95 O films was investigated. The result shows that the main N-related defect is N O at low N content which contributes to p-type conductivity. When the N content increases, N O acceptors combine with N i to form low-energy substitutional diatomic molecules on the O sites, i.e. (N 2 ) O donors. The net hole concentration decreases because holes are compensated by electrons. The conduction finally becomes n-type. The compensation of N O acceptors by (N 2 ) O explains the difficulty to achieve high p-type conduction by N doping in ZnO-type materials. © 2012 The Electrochemical Society.