Toppan Printing Co., Ltd. has successfully driven an electrophoretic type of electronic paper by using a solution-processed oxide semiconductor TFT (thin film transistor) array at a low process temperature.

The oxide semiconductor layer was processed using a vacuum-free solution process, while other layers were fabricated using a standard vacuum deposition process. The solution semiconductor material is developed by Creavis Technologies & Innovation, the strategic research and development unit of Evonik Industries AG in Germany.

In collaboration with Evonik, the process temperature of the semiconductor has been suppressed at 270 degrees, which is 100 degrees lower than the reported value. This result indicates that, instead of traditional glass materials, a solution processed TFT can be fabricated using flexible plastic films, which enable flexible displays. Moreover, the vacuum-free process will dramatically decrease the equipment and process costs for the TFT array.

In order to realize thin, light-weight and flexible displays, Toppan Printing will focus on the research and development of flexible TFTs and innovations in the fabrication process. In collaboration with Casio Computer Ltd., with which Toppan Printing is currently cooperating in the field of displays, Toppan Printing will accelerate the commercialization of flexible displays.