The two-finger stacked bottom gate and top gate fin indium gallium zinc aluminum oxide thin-film transistors (IGZAO TFTs) were fabricated. Since the bottom induced channel layer and the top induced channel layer were formed in the stacked TFTs using the bottom gate and the top gate, simultaneously. Consequently, drain-source current and transconductance of the stacked TFTs were enhanced about twice as those of the bottom gate TFTs and the top gate TFTs. The optimal performances of the stacked TFTs could be obtained, when the whole channel layer was induced as the carrier transportation path.