Beschreibung:
<jats:title>Abstract</jats:title><jats:p>High‐performance, coplanar amorphous In<jats:sub>0.5</jats:sub>Ga<jats:sub>0.5</jats:sub>O (a‐IGO) thin film transistor (TFT) on a polyimide (PI) substrate deposited by spray pyrolysis (SP) is reported. The SP a‐IGO film deposited at 370 °C has less than 8% nanocrystalline‐In<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> dots and a mass density of 6.6 g cm<jats:sup>−3</jats:sup>. The a‐IGO TFT on PI exhibits linear mobility over 30 cm<jats:sup>2</jats:sup> V<jats:sup>−1</jats:sup> s<jats:sup>−1</jats:sup> and a negligible shift in threshold voltage (Δ<jats:italic>V</jats:italic><jats:sub>TH</jats:sub> = <0.3 V) under positive bias (+20 V) at 60 °C for 1 h. The TFT performance is stable even when bent to a radius of ≈1 mm. The X‐ray photoelectron spectroscopy results of the SP a‐IGO deposited at 370 °C indicate the O‐vacancy (V<jats:sub>o</jats:sub>) related defects of 25.79% and hydroxyl (OH) at less than 3%, indicating a good active/gate insulator interface. A seven‐stage ring oscillator made of SP a‐IGO TFTs exhibits a high oscillation frequency (>2.3 MHz) with a low propagation delay time of ≈30 ns per stage at a supply voltage (<jats:italic>V</jats:italic><jats:sub>DD</jats:sub>) of 15 V. The fabricated gate shift register circuit works up to the last stage without any decrement of the input voltage (15 V) with rising and falling times less than 0.8 µs. Therefore, the coplanar a‐IGO TFT by SP deposited at 370 °C is a promising candidate for low‐cost, flexible TFT backplanes of foldable electronics.</jats:p>