1 research outputs found
High Performance, Low Temperature Solution-Processed Barium and Strontium Doped Oxide Thin Film Transistors
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 InBaĀ(Sr)ĀZnO 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 Ā°C we achieve high field-effect
electron mobility up to 26 cm<sup>2</sup> V<sup>ā1</sup> s<sup>ā1</sup>. We show that it is possible to solution-process
these materials at low process temperature (225ā200 Ā°C
yielding mobilities up to 4.4 cm<sup>2</sup> V<sup>ā1</sup> s<sup>ā1</sup>) and demonstrate a facile āink-on-demandā
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