56.3: Ultra‐flexible Amorphous Indium‐Gallium‐Zinc Oxide (a‐IGZO)

Abstract

Abstract In this work, we demonstrate an ultra‐flexible a‐IGZO TFT on PEN plastic substrate. The a‐IGZO TFT could be operated well with almost unchanged performance after banding at radius of 4 mm (strain∼1.5%) for more than 100 times. This was implemented the utilization of polymer gate dielectric, poly(4‐vinylpheonol) (PVP). The PVP was then demonstrated with no damage after plasma process equivalent the the a‐IGZO deposition process. Due to the large Young's modulus difference, the stress was believed mainly within polymer gate dielectric. Therefore, after bending, the a‐IGZO was not damaged. In addition to the ultra‐flexibility, the a‐IGZO TFT exhibit mobility around 1.3 cm 2 /Vs with nearly 6 orders of magnitude current on/off ratio at operation of 10V. The mobility could be further increase by fine‐tuning the a‐IGZO deposition condition. Combing the ultra‐flexibility and the acceptable performance, this technology is suitable to integrate into LCD or OLED implementing ultraflexible display.