Properties of Low Temperature Deposited ZnO Thin Films on the Glass Substrate by Cathodic Arc Plasma Technology with Different Film Thickness

摘要

We deposited un-doped ZnO films on the glass substrate at a low temperature (<75℃) by using cathodic arc plasma technique. The effect of the film thickness (130, 200, 370, 420, 550 nm) on the microstructure, optical and electrical properties of the deposited ZnO films was investigated and discussed. XRD patterns showed that the films revealed a polycrystalline hexagonal wurtzite crystal structure with a strong diffraction peak of ZnO (002) and the crystallite size of ZnO films was enlarged by increasing the thickness. All films showed an average transmittance over 80% in the visible region and calculated values of the band gap were around 3.34 to 3.31 eV when the film thickness increased. The lowest resistivity about 6.26 × 10~(-3) Ω-cm could be achieved for the un-doped ZnO film with thickness of 550 nm. It was found the film thickness plays an important role on the optical as well as electrical properties.