Low temperature deposition of ZnO semiconductor thin films on a PEN substrate by a solution process

Low-temperature processed ZnO semiconductor films were deposited onto polyethylene naphthalate (PEN) plastic substrates by a spin coating technique using ZnO nanoparticle (NP) dispersion. The ZnO nanoparticles (NPs) were synthesized by the hydrothermal method, and solution processable dispersion was used to disperse the ZnO NPs in a mixed aqueous solution with a polyvinylpyrrolidone (PVP) dispersant agent. The effects of annealing temperature (from 150°C to 250°C) on the electrical properties of glass/ZnO film samples are reported. The optimized annealing condition (200°C) was applied for ZnO film deposited on a PEN substrate. Comparative electrical properties of the PEN/ZnO film samples before and after bending tests are also presented. Experimental results show that the electrical resistivity of the PEN/ZnO film sample was 1.91 × 104 Ω cm with a Hall mobility of 45.9 cm2/Vs. After bending tests, the electrical resistivity was raised to 1.26 × 105 Ω cm and the Hall mobility was reduced to 31.0 cm2/Vs.