The thin-film transistors (TFTs) with back-channel etched (BCE) type enable channel length to be narrow and reduce parasitic capacitances owing to its shorter overlaps between the gate and source/drain (S/D) electrodes. In this study, a high-performance BCE-type oxide thin-film transistor was proposed for investigation. A novel stacked double layer In-W-O (IWO) / In-W-Zn-O (IWZO) channel structure was fabricated and developed. Respectively, IWZO exhibits a high resistance to back-channel etching damage and IWO channel achieve a high mobility. The double layer IWO/IWZO TFTs are promising candidates for driving active matrix organic light-emitting diode (AMOLED) and high resolution display applications in the future. The double layer IWO/IWZO TFTs with S/D pattern by H₂O₂ + KOH can exhibit the high-performance electrical characteristic. The field-effect mobility (µ_FE) ~ 21.1cm²/V-s, subthreshold swing (S.S.) ~ 0.15 V/dec., threshold voltage (V_TH) ~ -0.092 V, and on/off ratio ~ 4.88×10⁸ can be achieved.