Thin film transistor

Abstract

A thin film transistor and a fabrication method therefor, which thin transistor includes: a stepped substrate provided with a sidewall between upper portion and lower portions thereof; an active layer formed on the substrate, a gate insulation film on the active layer; a gate electrode formed on the gate insulation film corresponding to an upper part of the sidewall of the substrate; an insulation film formed on a part of the gate insulation film between the gate electrode and the lower portion of the substrate; and impurity regions formed in the active layer corresponding, to the upper and lower portions of the substrate. The impurity regions are formed by a self-aligned process using an additional mask, which controls the length of channel and offset regions in accordance with the thicknesses of the gate electrode and insulation film, respectively, for thus obtaining a more stabilized offset current and accordingly improving the reliability and reproducibility of the semiconductor device.

Dependencies are inferred from the claim text.