Electrical and optical properties of annealed AlSnZnO films deposited using radio frequency magnetron cosputtering system

Using a dual aluminum zinc oxide (AZO) target and tin dioxide (SnO₂) target, 200-nm-thick aluminum-tin-zinc-oxide (ATZO) films were deposited onto quartz substrates by a radio frequency magnetron cosputtering system. After measuring X-ray diffraction patterns, carrier concentration, carrier mobility, room-temperature photoluminescence spectra, and ultraviolet–visible–near infrared spectra of the ATZO films without and with thermal annealing treatment in an oxygen ambience for 10 min at various temperatures, the annealing effects were demonstrated. Correlations among crystalline structures, electrical properties, optical properties, and annealing temperatures were observed. As the annealing temperature increased from 200 °C to 300 °C, the atoms of ATZO films gained more kinetic energy and more surface mobility to occupy stable positions. However, by further increasing the annealing temperature to 400 °C, the bonds in ATZO films became broken rather than enabling the atoms to remain in their corresponding stable positions. Consequently, the best properties were obtained for ATZO films annealed at 300 °C.