RETRACTED: Dependence of the structural and optical properties of ZnO thin films on the substrate temperature in atomic layer deposition and post-annealing

Abstract

In this paper, the effects of substrate temperature during atomic layer deposition (ALD) and post-annealing temperature on microstructures and optical properties were investigated using X-ray diffraction (XRD), photoluminescence (PL) and scanning electron microscopy (SEM) techniques. The temperature window for ALD was found to be 130-180°C. The growth rate of ZnO film was increased as the substrate temperature was increased, and crystallinity was found to be strongly dependent on the substrate temperature among all the process parameters of ALD. Crystallinity of the ZnO thin film was observed to be improved with increase in the process time per ALD cycle or with post-annealing treatment. The grain size of the ZnO film tended to increase and the grain shape tended to change from a worm-like longish shape to a round one as the annealing temperature increased from 600 to 1000 °C.