RF Power and Thermal Annealing Effect on the Properties of Zinc Oxide Films Prepared by Radio Frequency Magnetron Sputtering

Polycrystalline zinc oxide (ZnO) films were prepared by radio frequency (RF) magnetron sputtering under different powers. The XRD results showed that ZnO crystallite size along c-axis decreased by 43% with deposition power increased from 60 W to 300 W, increased 36% with annealing temperature rising to 400∘C . TDS measurement revealed that the desorption peaks of both atomic Zn (60 W-deposited) and oxygen molecule (180 W and 300 W-deposited) obtained from ZnO films were originated from 300∘C . When annealing temperature was higher than 300∘C , the sheet resistance dramatically decreased, and compressive stress in the (002) plane changed to tensile stress as well. The comparison measurements of ZnO films crystallinity strongly suggested that both lower deposition power and certain thermal annealing temperature over 300∘C would contribute to the formation of high quality ZnO films.