fig7

Figure 7. Flexible MO TFTs employing island structure. (A) Schematic of the three different types of top gate a-IGZO TFTs, photograph of island a-IGZO TFT with passivation. Transfer characteristics of three types of a-IGZO TFTs before the bending test. Changes in electrical properties of the TFTs repeated bending cycle. Reproduced with permission^[102]. Copyright 2021, American Chemical Society; (B) Schematic of a-IGZO TFT fabricated with mesa-island structure. 3D image for mechanical stress distribution of mesa-island structure using FEA modeling to analyze mechanical stress. Normalized electrical characteristics of a-IGZO TFTs on island structure and conventional structure before and after 10,000 bending cycles under a bending radius of 125 μm. Reproduced with permission^[33]. Copyright 2020, Wiley-VCH; (C) Schematic of island structure formation of a-IGZO TFTs. Transfer characteristics of the devices with island structure and the electrical responses of the devices as a function of the accumulated stress after 100,000 bending cycles at a radius of 2.0 mm. Reproduced with permission^[193]. Copyright 2016, Elsevier. MO: Metal oxide; TFTs: thin-film transistors; IGZO: indium gallium zinc oxide; FEA: finite-element analysis.