Improved Split C–V Technique for Effective Mobility Extraction in Self-Aligned Top-Gate Amorphous InGaZnO TFTs with Short Channel

Abstract

In this paper, we evaluate the feasibility of the split capacitance-voltage (C–V) technique for mobility extraction in self-aligned top-gate (SATG) amorphous InGaZnO (a-IGZO) thin-film transistors (TFTs) with short channel down to 5 μm. The accuracy of the effective mobility (μeff) extraction approach is greatly enhanced by properly de-embedding the disturbances, including channel length reduction (ΔL), inner fringing capacitance (Cif), and source/drain access resistance (RSD). The results show that the parasitic bias-dependent RSD and Cif in the inner fringe regions of the channel account for the underestimation of μeff on short-channel devices.