Abstract
Foldable and rollable displays are of increasing interest recently. I will discuss the key technologies of TFTs for those applications. Non-laser detach technology was developed by using a CNTGO buffer layer inserted into PI substrate which helps easy detach and more self-standing plastic substrate [1]. We made oxide and LTPS TFTs on PI substrate using CNTGO buffer layer and investigated the effect of bending and rolling on the electrical properties of TFTs. Tensile stress is found to give more change to the TFT performance for both LTPS and oxide TFTs compared to compressive stress [2]. These results are related with out-folding or in-folding of smartphone displays. The split of both source/drain and semiconductor layer is important for more flexible TFTs [3]. The device performance is also improved a lot by splitting for etch-stopper oxide TFT [4]. The TFT in neutral plane is also very robust under bending [5]. I will discuss one directional stretchable TFT array for high resolution biosensors and thin-film encapsulation of top-emission OLED using SiNx/polymer multilayer for highly foldable OLED.
Jin Jang is a Professor at Department of Information Display of Kyung Hee University. He developed world 1st full color TFT-LCD on plastic, Flexible AMOLED and Transparent AMOLED which were presented at the SID Conferences. He is the author or co-author of over 1000 papers, of which over 600 are in SCI Journals such as Nature, Advanced Materials, Advanced Functional Materials, Energy Environmental Science, APL and EDL. He is currently a Director of Advanced Display Research Center (ADRC) and a Fellow of SID and had served as a General Chair of IMID and SID Display Week.