Intrinsic field-effect mobility in thin-film transistor with polycrystalline In2O3 channel based on transfer length method

Abstract

Field-effect mobility (μFE), calculated using transconductance in thin-film transistors (TFTs) includes error factors from determination of channel width/length and parasitic resistance (Rs/d) at source and drain regions. The apparent μFE is generally underestimated owing to the drain voltage drop due to Rs/d, which in turn, is caused by a low channel resistance (Rch) in high-mobility channels. This letter describes the extraction of intrinsic μFE (μFEi) in TFTs with polycrystalline In2O3 channels by separating Rs/d and Rch, based on the transfer length method. Using the proposed methodology, we obtained a high μFEi (>100 cm2 Vs−1) from TFT.