Growth of p-type ZnO thin films by using an atomic layer epitaxy technique and NH_3 as a doping source

摘要

Nitrogen-doped, p-type ZnO thin films have been grown successfully on sapphire (0001) substrates by atomic layer epitaxy (ALE) using Zn (C_2H_5)_2 [Diethylzinc, DEZn], H_2O and NH_3 as a zinc precursor, an oxidant and a doping source gas, respectively. The lowest electrical resistivity of the p-type ZnO films grown by ALE was 210 Ω cm with a hole concentration of 3.41 x 10~(16) cm~(-3). Low temperature-photoluminescence analysis results support that the nitrogen ZnO after annealing is a p-type semiconductor. Also a model for change from n-type ZnO to p-type ZnO by annealing is proposed.