Effects of N₂O gas addition on the properties of ZnO films grown by catalytic reaction-assisted chemical vapor deposition

The influence of N₂O gas addition on the properties of zinc oxide (ZnO) films grown on a-plane (11–20) sapphire (a-Al₂O₃) substrates was investigated, using a chemical vapor deposition method based on the reaction between dimethylzinc and high-temperature H₂O produced by a catalytic H₂-O₂ reaction on platinum (Pt) nanoparticles. The addition of N₂O was found to increase the size of the crystalline facets and to improve the crystal orientation along the c-axis. The electron mobility at 290 K was also increased to 234 cm²/Vs following the addition of N₂O gas at a pressure of 3.2 × 10⁻³Pa. In addition, the minimum full width at half maximum of the most intense photoluminescence peak derived from neutral donor bound excitons at 10 K decreased to 0.6 meV by the addition of N₂O gas at a pressure of 3.1 × 10⁻²Pa