Streamlined Inkjet-Printing of Stretchable Organic Photodetectors

Abstract

The rapid development of the Internet of Things (IoT), artificial intelligence, robotics, and wearable electronics has created new challenges and increased the demand for advanced sensing technologies. These sensors must not only exhibit tailored performance but also offer new properties like stretchability and flexibility while being compatible with industrial manufacturing. In this work, a streamlined and simplified method is introduced for fabricating stretchable Organic Photodiodes (OPDs) relying solely on industry-grade inkjet-printing. It is demonstrated that printed stiff islands effectively decouple strain from the stretched substrate and serve as a chemically resistant and mechanically rigid platform for printed OPDs. Printing difficulties that arose while processing the Ag electrodes on the curved island surfaces are overcome by a two-step printing process. Finally, the study reports fully printed OPDs exhibiting peak responsivities (λ = 730 nm) of 340 mA W−1 and specific detectivities (D*) of 2.8 · 1011 Jones at 100 Hz, both measured at −2 V. The light sensors remained functional for over 600 mechanical stretching cycles at strains up to 7%.