Effect of rf power on structural, optical and morphological properties of ultrathin undoped ZnO films deposited by rf magnetron sputtering

Abstract

Undoped ZnO Ultra thin films were deposited on glass substrates by rf magnetron sputtering. Thin films were deposited at various rf powers 50, 75, 100 and 125W. The measured thickness of the films were less than 50nm. Structural properties were studied by X-ray diffraction (XRD) which confirmed that the films were crystalline with a (002) preferential orientation. The optical properties were studied by UV-Vis spectrophotometry in the 300-1000nm range, obtaining an average transmittance around 70 %. The AFM characterization revealed that rms roughness value increases with rf power.