Preparation and Properties of N-Doped p-Type ZnO Films by Solid-Source Chemical Vapor Deposition with the c-Axis Parallel to the Substrate

We report on N-doped p-type ZnO films with the c-axis parallel to the substrate. ZnO films were prepared on an α-Al₂O₃ (0001) substrate by solid-source chemical vapor deposition (CVD). Zn(CH₃COO)₂.2H₂O was used as the precursor and CH₃COONH₄ as the nitrogen source. Growth temperature is varied from 300°C to 600°C. The as-grown ZnO film deposited at 500°C showed p-type conduction with its resistivity of 42 Ωcm, carrier density 3.7 x 10¹⁷cm^-3 and Hall mobility 1.26cm²V^-1.s^-1 at room temperature, which are the best properties for p-type ZnO deposited by CVD. The p-type ZnO film possesses a transmittance about 85% in the visible region and a band gap of 3.21 eV at room temperature.