Evolution Mechanisim of Microstructure of AZO Thin Films Prepared by Reactive Magnetron Sputtering

ZnO∶Al(AZO) thin films were grown by reactive DC magnetron sputtering technique under various oxygen flow ratio at room temperature.The effect of oxygen flow on phase,morphology and structure of the deposited films were systematically analyzed by XRD,SEM and TEM,respectively.The thin films deposited under 2.5 sccm O2 flows show AZO/Zn(AZO) bilayers structure.As the oxygen flow is 3.5 sccm,the AZO thin films with good visible transparency and low resistivity exhibited the c-axis(002) oriented polycrystalline films.As the oxygen flow is 5.0 sccm,Al2O3 nanoparticles were formed in AZO films with visible transparency and high resistivity and disappeared after annealing at 400 ℃.