Fabrication of the ZnO thin films using wet-chemical etching processes on application for organic light emitting diode (OLED) devices

We deposited ZnO thin films at room temperature by RF magnetron sputtering method with home-made targets, and for application tests using these films as transparent conductive oxide (TCO) anodes, wet-chemical etching behaviors of ZnO films were also investigated using various chemicals. In order to fabricate ZnO-based OLED devices, various etchants such as HCl, HNO3, H2SO4 and H3PO4 have been studies for the wet etching of ZnO thin film. In this experiment, we introduced two new different chemicals as etchants, ferric chloride (FeCl3 ∙ 6H2O) and oxalic acid (C2H2O4) which were controlled with various concentrations in ZnO etching process and showed an anisotropy etching shape of ZnO films.