Flexible Electronics using Liquid Silicon

A team led by EEMCS associate professor Ryoichi Ishihara has successfully fabricated flexible, super-fast transistors on plastic foil. Their technology considerably improves on transistor fabrication based on printing techniques, which has limited application for flexible electronic devices. The innovation opens new paths for flexible displays and many other applications, such as implantable sensors, flexiblesmart sensor tags with ultra-high frequency RF-ID, and flexible, stable solar-cells with high efficiency. A flexible polyimide substrate is coated with a special solution called ‘liquid silicon’. Using laser recrystallisation, a thin polysilicon layer is prepared with 3μm sized grains at predetermined positions. Transistors fabricated inside the grains show an unparalleled high carrier mobility of 461 cm2/Vs.