O2 /HMDSO-Plasma-Deposited Organic-Inorganic Hybrid Film for Gate Dielectric of MgZnO Thin-Film Transistor

Abstract

An organic–inorganic hybrid film is deposited from O2/HMDSO plasma. The SiOSi/SiCH3 FTIR absorption ratio of this film increases with the process power and O2/HMDSO precursor flow ratio, resulting in a more inorganic-like film. This hybrid film is used as the gate dielectric of MgZnO TFTs. As the SiOSi/SiCH3 FTIR absorption ratio of the gate dielectric increases, the gate leakage current decreases, on/off current ratio increases, threshold voltage increases, and subthreshold swing increases. High SiCH3 bonding content in the gate dielectric improves TFT switching but deteriorates gate insulation, resulting in increased gate leakage current and decreased on/off current ratio.