The etch rate and surface morphology of Zn-containing oxide and HfO2 films after wet chemical etching were investigated. ZnO could be easily etched using each acid tested in this study, specifically sulfuric, formic, oxalic, and HF acids. The etch rate of IGZO was strongly dependent on the etchant used, and the highest measured etch rate (500 nm/min) was achieved using buffered oxide etchant at room temperature. The etch rate of IGZO was drastically increased when sulfuric acid at concentration greater than 1.5 molar was used. Furthermore, etching of HfO2 films by BF acid proceeded through lateral widening and merging of the initial irregular pits.