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 o C 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.