Numerical Modelling on the Effect of Temperature on MOCVD Growth of ZnO Using Diethylzinc and Tertiarybutanol

The dynamic growth of MOCVD-grown ZnO thin films under temperature effect was systematically investigated by a numerical approach using computational fluid dynamics (CFD) technique. A three-dimensional (3D) reactor-scale model was developed to determine the growth rate and uniformity of ZnO thin film in the temperature range of 593 K to 713 K. The mixed-convection flow and heat transfer inside the reactor chamber were assessed. The results showed that as the temperature increased, ZnO thickness increased initially before decreasing. At 673 K, the highest deposition rate with acceptable uniformity was achieved. The admixture of transverse and longitudinal rolls was observed for the flow conditions. Temperature variations were found to directly affect the axial and lateral uniformity of deposition, but had a minor impact on the size and position of transverse rolls. Experimental verification studies were conducted, and high-quality ZnO films were successfully fabricated by using diethylzinc (DEZn) and tertiarybutanol (t-BuOH) as precursors; it was found that the comprehensive thickness and structural properties of ZnO deposited at temperature of 673 K are preferred. Experimental results and numerical simulations exhibited good agreement.