Surface Oxidation Effect During high Temperature Vacuum Annealing on the Electrical Conductivity of ZnO thin Films Deposited by ALD

The chemical, electrical, and optical properties of ZnO and Al-doped ZnO films after high temperature annealing were studied. The resistivity increased significantly after annealing at 600℃ under 10-10 Torr atmosphere. The mechanism of the resistivity change was explored using photoemission spectroscopy and photoluminescence spectrometer. The results indicated that the amount of oxygen deficient region O–Zn bonds decreased and oxygen vacancy was decreased after the high temperature vacuum annealing. The increase in the resistivity of ZnO and Al-doped ZnO films was resulted from the decrease in carrier concentration due to a decrease in the amount of oxygen deficiency.