Pressure dependence and micro-hillock formation of ZnO thin films grown at low temperature by MOCVD

ZnO thin films were grown at a reduced growth temperature on a Si substrate by low-pressure metalorganic chemical vapor deposition. The effects of the reactor pressures and the formation of micro-hillocks on the characteristics of the film were investigated. The ZnO films grown at 210 °C showed mass-transport limited growth behavior and a faceted surface morphology. It was found that the effect of the micro-hillocks on the structural, optical, and electrical properties can be ignored. While the sample grown at 10 Torr showed transparent conductive oxide properties, the sample grown at 3 Torr showed suitable characteristics for use as an ultraviolet emitter.