TW274147B - Amorphous silicon thin film transistor structure and fabrication process thereof - Google Patents

Abstract

A fabrication method of thin film transistor comprises the steps of: depositing one first metal layer on insulating substrate, via photolithography etching the first metal layer to form gate, in which the etch is one overetch by liquid phase deposition growth to grow one oxide with thickness equal to gate's, then removing phtoresist to be planar around the gate, in sequence depositing the first silicon nitride, intrinsic amorphous silicon, n-type amorphous and the second metal layer; via photolithography etching the second metal layer and n-type amorphous to define channel area; via another photolithography etching intrinsic amorphous silicon, the first silicon nitride and silicon oxide to leave island thin film transistor around channel; at last depositing the second silicon nitride , and via photolithography and etching to define joint point of source/drain; in which by liquid phase deposition growth making area round gate planar to avoid generating leakage one gate edge, increasing field effect mobility, decreasing threshold voltage and increasing on/off current ratio.