Pressureless sintering of ZnO thin film on plastic substrate via vapor annealing process at near-room temperature

In this work, Vapor Annealing Sintering (VAS) process was introduced for low-cost pressureless producing dense Zinc Oxide (ZnO) thin films deposited from nanoparticles at near-room temperature (50 °C). Spontaneous densification evolution from nanoparticulate to a dense film via a dissolution-diffusion-reprecipitation mechanism was observed exposing ZnO layers to the vapor of an acetic acid aqueous solution at isothermal condition. The influence of the annealing on the optical properties of the treated films was investigated in order to study the structural changes. The proposed method can allow new opportunities for simple and low-cost ceramics thin film manufacturing also involving pressure and temperature-sensitive materials.