Development of flexible displays using back‐channel‐etched In–Sn–Zn–O thin‐film transistors and air‐stable inverted organic light‐emitting diodes

We developed flexible displays using back-channel-etched In–Sn–Zn–O (ITZO) thin-film transistors (TFTs) and air-stable inverted organic light-emitting diodes (iOLEDs). The TFTs fabricated on a polyimide film exhibited high mobility (32.9 cm2/Vs) and stability by utilization of a solution-processed organic passivation layer. ITZO was also used as an electron injection layer (EIL) in the iOLEDs instead of conventional air-sensitive materials. The iOLED with ITZO as an EIL exhibited higher efficiency and a lower driving voltage than that of conventional iOLEDs. Our approach of the simultaneous formation of ITZO film as both of a channel layer in TFTs and of an EIL in iOLEDs offers simple fabrication process.

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