With the advent of the Internet of Things (IoT) era, strong demand has grown for wearable and transparent displays that can be applied to various fields such as augmented reality (AR) and skin-like thin flexible devices. However, previous flexible transparent displays have posed real challenges to overcome, which are, among others, poor transparency and low electrical performance. To improve the transparency and performance, past research efforts have tried to use inorganic-based electronics, but the fundamental thermal instabilities of plastic substrates have hampered the high temperature process, an essential step necessary for the fabrication of high performance electronic devices.
Ref: Skin-Like Oxide Thin-Film Transistors for Transparent Displays. Advanced Functional Materials (4 July 2016) | DOI: 10.1002/adfm.201601296
Flexible transparent display is a promising candidate to visually communicate with each other in the future Internet of Things era. The flexible oxide thin-film transistors (TFTs) have attracted attention as a component for transparent display by its high performance and high transparency. The critical issue of flexible oxide TFTs for practical display applications, however, is the realization on transparent and flexible substrate without any damage and characteristic degradation. Here, the ultrathin, flexible, and transparent oxide TFTs for skin-like displays are demonstrated on an ultrathin flexible substrate using an inorganic-based laser liftoff process. In this way, skin-like ultrathin oxide TFTs are conformally attached onto various fabrics and human skin surface without any structural damage. Ultrathin flexible transparent oxide TFTs show high optical transparency of 83% and mobility of 40 cm2 V−1 s−1. The skin-like oxide TFTs show reliable performance under the electrical/optical stress tests and mechanical bending tests due to advanced device materials and systematic mechanical designs. Moreover, skin-like oxide logic inverter circuits composed of n-channel metal oxide semiconductor TFTs on ultrathin, transparent polyethylene terephthalate film have been realized.