Ultrathin, Ultra-Conformable, and Free-Standing Tattooable Organic Light-Emitting Diodes

A novel tattooable, ultrathin, green organic light-emitting diode (OLED) fabricated on top of commercial temporary tattoo paper, is demonstrated. The transfer mechanism relies on dissolution of the sacrificial layer typically incorporated in paper-tattoos. The ready-to-use device can be stored on the tattoo substrate and released on the target surface at a later time, simply by a slight wetting of the tattoo paper with water. This approach provides a quick and easy method of transferring OLEDs on virtually any surface. This is particularly appealing, in perspective, for on-skin and disposable electronic applications. The proof of concept demonstrates, for the very first time, the feasibility of ultrathin operational OLED tattoos. While the performance of such devices is not yet comparable with that of OLEDs on rigid or flexible non-tattooable substrates, the results show the potential for an OLED tattoo technology in integrated conformable electronic circuits.