The Performance Improvement of N-2 Plasma Treatment on ZrO2 Gate Dielectric Thin-Film Transistors with Atmospheric Pressure Plasma-Enhanced Chemical Vapor Deposition IGZO Channel

Abstract

The aim of this paper is to illustrate the N-2 plasma treatment for high-kappa ZrO2 gate dielectric stack (30 nm) with indium-gallium-zinc-oxide (IGZO) thin-film transistors (TFTs). Experimental results reveal that a suitable incorporation of nitrogen atoms could enhance the device performance by eliminating the oxygen vacancies and provide an amorphous surface with better surface roughness. With N-2 plasma treated ZrO2 gate, IGZO channel is fabricated by atmospheric pressure plasma-enhanced chemical vapor deposition (AP-PECVD) technique. The best performance of the AP-PECVD IGZO TFTs are obtained with 20 W-90 sec N-2 plasma treatment with field-effect mobility (mu(FET)) of 22.5 cm(2)/V-s, subthreshold swing (SS) of 155 mV/dec, and on/off current ratio (I-on/I-off) of 1.49x10(7).