Mechanically flexible nonvolatile memory thin-film transistors using oxide semiconductor active channels on ultrathin polyimide films

We overview mechanically flexible nonvolatile memory thin-film transistors (TFTs) for next-generation flexible and stretchable electronic applications. The proposed memory TFTs are featured to be implemented by oxide semiconductor thin films and operated with charge-trap-assisted nonvolatile memory operations on ultrathin colorless polyimide films. The fabrication processes and related technical issues are described for realizing high-performance flexible memory TFTs. We also discuss the memory devices' characteristics and the mechanical flexibility of the fabricated memory TFTs. The novel approaches in material and device structure viewpoints are introduced for further improvements in mechanical flexibility. We finally summarize the remaining issues and future perspectives.