Improvement in the bias stability of amorphous indium gallium zinc oxide thin-film transistors using an O2 plasma-treated insulator

The effects of an O-2 plasma-treated SiNX-based insulator on the interfacial property and the device performances of amorphous indium gallium zinc oxide thin-film transistors (a-IGZO TFTs) were investigated. We tried to improve the interfacial characteristics by reducing the trap density between the SiNX gate insulator and a-IGZO channel by the O-2 plasma treatment. The plasma treated- device performances were remarkably improved. The drastic improvements obtained for the O-2 plasma-treated a-IGZO TFTs included excellent bias stability as well as a high field effect mobility (mu(FE)) of 19.4 cm(2)/V s, an on/off current (I-ON/I-OFF) of 108, and a subthreshold value (S) of 0.5 V/decade. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3167816]