Effect of the Bias Voltage on the Structure, Mechanical, Electronic and Optical Properties of the Low Temperature ZnO Thin Films Deposited by Using Cathodic Vacuum Arc Deposition System on Plastic Substrates

Abstract

The un-doped zinc oxide (ZnO) films on the polyethylene terephthalate (PET) substrate at a low temperature (<75°C) by using cathode vacuum arc deposition (CVAD) system with different negative substrate bias voltage applied between 0 and -100 V. The material, mechanical, optical and electrical properties were investigated and discussed. The results show that all ZnO thin films have (002) preferred orientation, an average transmittance was over than 70 % in the visible region. Calculated band gap values are all around 3.2 eV with the different substrate bias voltages. The ZnO thin films with resistivities as low as 10-3 Ω*cm have been obtained by adjusting the substrate bias voltage on the plastic substrates.