Structural, electrical and optical properties of N-doped ZnO films synthesized by SS-CVD

Abstract

N-doped p-type ZnO films have been synthesized on α-Al 2O 3 (0 0 0 1) substrate by solid-source chemical vapor deposition using Zn(CH 3COO) 2·2H 2O as the precursor and CH 3COONH 4 as the nitrogen source. The properties for ZnO films are dependent greatly on the growth conditions. Results show that the best electrical properties of the p-type film, such as carrier density N=9.8×10 17 cm −3 , resistivity ρ=20 Ω cm and Hall mobility μ=0.97 cm 2/ V s , were induced at the substrate temperature of 500°C with a precursor temperature of 250°C and a nitrogen source of 150°C, under which the highest mixed orientation for (1 0 0) and (1 1 0) planes of films was also achieved. The p-type ZnO films possess a transmittance of about 90% in visible region and a band gap of about 3.20 eV at room temperature.