Polymer field-effect transistors operated in the n-channel model with a top-gate/bottom-contact are processed using a solution method.The transistor performance depends on the gate dielectric layer.A high performance polymer transistor is achieved,with the saturated electron mobility of about 0.46 cm~2/Vs,threshold voltage nearly OV and subthreshold sway of about 0.9V/decade,employing a polystyrene(PS) dielectric layer.The transistor performances are further improved with increasing current and lower operation voltages by utilizing a bi-layer gate dielectric,comprising a thin PS dielectric layer adjacent to the semiconductor to minimize the density of the interface traps for obtaining a small V_T,a large μ and a poly(methyl methacrylate)(PMMA)dielectric layer with a relatively high-k adjacent to the gate electrode for enlarging the capacitance,processed from the orthogonal solvents. Polymer field-effect transistors operated in the n-channel model with a top-gate / bottom-contact are processed using a solution method. The transistor performance depends on the gate dielectric layer. A high performance polymer transistor is achieved, with the saturated electron mobility of about 0.46 cm ~ 2 / Vs, threshold voltage almost OV and subthreshold sway of about 0.9V / decade, employing a polystyrene (PS) dielectric layer. transistor performance are further improved with increasing current and lower operating voltages by utilizing a bi -layer gate dielectric, comprising a thin PS dielectric layer adjacent to the semiconductor to minimize the density of the interface traps for obtaining a small V_T, a large μ and a poly (methyl methacrylate) (PMMA) dielectric layer with a relatively high-k adjacent to the gate electrode for enlarging the capacitance, processed from the orthogonal solvents.