Improved Electrical Performance of an Oxide Thin-Film Transistor Having Multistacked Active Layers Using a Solution Process

Thin-film transistors (TFTs) with multistacked active layers (MSALs) have been studied to improve their electrical performance. The performance enhancement with MSALs has been attributed to higher film density in the effective channel; the density was higher because the porosities of the sublayers were reduced by filling with solution. The proposed TFT with MSALs exhibited an enhanced field-effect mobility of 2.17 cm(2)/(V s) and a threshold voltage shift under positive bias stress of 8.2 V, compared to 1.21 cm(2)/(V s) and 18.1 V, respectively, for the single active layer TFT.