title: High Performance, Low Temperature Solution-Processed Barium and Strontium Doped Oxide Thin Film Transistors.
abstract: Amorphous mixed metal oxides are emerging as high performance semiconductors for thin film transistor (TFT) applications, with indium gallium zinc oxide, InGaZnO (IGZO), being one of the most widely studied and best performing systems. Here, we investigate alkaline earth (barium or strontium) doped InBa(Sr)ZnO as alternative, semiconducting channel layers and compare their performance of the electrical stress stability with IGZO. In films fabricated by solution-processing from metal alkoxide precursors and annealed to 450 °C we achieve high field-effect electron mobility up to 26 cm2V-1s-1. We show that it is possible to solution-process these materials at low process temperature (225-200 °C yielding mobilities up to 4.4 cm2V-1s-1) and demonstrate a facile "ink-on-demand" process for these materials which utilizes the alcoholysis reaction of alkyl metal precursors to negate the need for complex synthesis and purification protocols. Electrical bias stress measurements which can serve as a figure of merit for performance stability for a TFT device reveal Sr- and Ba-doped semiconductors to exhibit enhanced electrical stability and reduced threshold voltage shift compared to IGZO irrespective of the process temperature and preparation method. This enhancement in stability can be attributed to the higher Gibbs energy of oxidation of barium and strontium compared to gallium.
authors: Cavendish Laboratory, Department of Physics, University of Cambridge , Cambridge CB3 0HE, United Kingdom.
authors: Kulbinder K
authors: KK
authors: Banger
authors: Cavendish Laboratory, Department of Physics, University of Cambridge , Cambridge CB3 0HE, United Kingdom.
authors: Rebecca L
authors: RL
authors: Peterson
authors: Panasonic Corporation , Osaka 571-8501, Japan.
authors: Kiyotaka
authors: K
authors: Mori
authors: Panasonic Corporation , Osaka 571-8501, Japan.
authors: Yoshihisa
authors: Y
authors: Yamashita
authors: Multivalent Ltd. , Eriswell, Suffolk IP27 9BJ, United Kingdom.
authors: Timothy
authors: T
authors: Leedham
authors: Cavendish Laboratory, Department of Physics, University of Cambridge , Cambridge CB3 0HE, United Kingdom.
authors: Henning
authors: H
authors: Sirringhaus