a-IGZO TFTs With Inductively Coupled Plasma Chemical Vapor Deposited ${\rm SiO}_{x}$ Gate Dielectric

In this brief, amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs) are fabricated at . Inductively coupled plasma chemical vapor deposition (ICP-CVD) is used to grow SiO_x gate dielectric of the a-IGZO TFTs. The fabricated devices exhibit a high saturation mobility of 26.85 cm²/V·s, a steep subthreshold swing of 0.145 V/decade, and an ON/OFF current ratio of 2.3×10⁷. Atomic force microscope and scanning electron microscope images show that the surface characteristics of the ICP-CVD SiO_x gate dielectric are much superior to those of the conventional plasma-enhanced CVD SiO_x. It is suggested that the superior surface characteristics of the ICP-CVD SiO_x are the main origin of the high performance of the a-IGZO TFTs with the ICP-CVD SiO_x gate dielectric.