Highly Robust Bendable Oxide Thin-Film Transistors on Polyimide Substrates via Mesh and Strip Patterning of Device Layers

5 years ago

Highly Robust Bendable Oxide Thin-Film Transistors on Polyimide Substrates via Mesh and Strip Patterning of Device Layers

Mallory Mativenga, Jin Jang, Daun Jeong, Suhui Lee

Advancement in thin-film transistor (TFT) technologies has extended to applications that can withstand extreme bending or folding. The changes of the performances of amorphous-indium-gallium-zinc-oxide (a-IGZO) TFTs on polyimide substrate after application of extreme mechanical bending strain are studied. The TFT designs include mesh and strip patterned source/drain metal lines as well as strip patterned a-IGZO semiconductor layer. The robustness of the a-IGZO TFTs with the strain of 2.17% corresponding to the radius of 0.32 mm is tested and no crack generation even after 60 000 bending cycles is found. The split of source/drain electrodes and semiconductor layer can improve the mechanical bending stability of the TFTs. This can be possible by using conventional TFT manufacturing process so that this technology can be easily applied to build robust TFT array for foldable displays. Extremely stable high-performance a-IGZO thin-film transistors (TFT) on plastic substrates are achieved by splitting S/D/G electrodes and the active semiconductor layer. When the S/D/G electrodes are patterned as metal mesh with strip-patterned a-IGZO layer, mechanical stability of the TFT can be greatly improved and thus there is no crack generation even after 60 000 bending cycles with the radius of 0.32 mm.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/adfm.201700437