Al-doped ZnO (AZO) film has high transmittance in the visible region

low resistance and better stability

so AZO films have been actively investigated for potential applications in a variety of opto-electronic devices

such as solar cells

flat panel displays

transparent heat mirrors and organic light-emitting diodes. The properties of ZnO film are critically dependent on various deposition parameters

such as radio-frequency power

working gas pressure

and substrate temperature

and so on

Among these factors

the study of influence of rf power on film properties is important to build on the understanding of the relationship between film properties and process conditions. In this paper

using ZnO mixed with Al

2

O

3

(2%) as target

thin AZO films were prepared on glass substrates by radio frequency magnetron sputtering at different rf powers of 40

80

120

160 and 200 W. The influence of sputtering power on structure

optoelectronic properties

thickness and thermal stability of thin AZO films were investigated by XRD

UV-Vis spectrophotometer

four point probe and instrument level. It was found that the AZO thin films with hexagonal wurtzite structure have a (002)

c

-axis preferential orientation

and the intensity of the (002) peak increase as the increase of RF power. For all of the AZO thin films

the average transmittance of the visible light is above 80%. The sheet resistance decreases as the increase of RF power. The films deposited at 160 and 200 W show good thermal stability

which change of sheet resis-tance before and after heat treatment is about 13%. This high thermal stability indicated that AZO films can replace thin Sn-doped In

2

O

3

(ITO) films applying in the touch screen.