Solution-Processed Rb-Doped Indium Zinc Oxide Thin-Film Transistors

Rubidium-doped indium zinc oxide thin film transistors (TFTs), including zirconium oxide gate dielectrics and In-Zn-O (IZO) channel deposition, were fabricated using a solution process. Electrical characteristics of Rb-doped IZO TFTs were improved significantly because of crystallinity enhancement with Rb doping. The optimal Rb-doping concentration to reach the highest field-effect mobility, ON/OFF current ratio, and a subthreshold slope were obtained at an Rb-doping concentration of 2 moles%. Compared with Li doping, Rb-doped IZO transistors exhibited less change of threshold voltage under bias stress.