Highly Stable Organic Transistors on Paper Enabled by a Simple and Universal Surface Planarization Method

In this work, operationally and mechanically stable organic field-effect transistors (OFETs) are demonstrated on aramid fiber-based paper enabled by a simple and universal surface planarization method. By employing a nanoimprint lithography-inspired surface smoothening method, rough aramid paper is successfully smoothened from a scale of several tens of micrometers to a sub-nanometer-scale surface roughness. Owing to the sub-nanometer-scale surface roughness of the aramid paper, the OFETs fabricated on the aramid paper exhibit decent field-effect mobility (0.25 cm ² V ⁻¹ s ⁻¹ ) with a high current on-to-off ratio (>10 ⁷ ), both of which are comparable with those of OFETs fabricated on rigid silicon substrates. Moreover, the OFETs fabricated on the aramid paper exhibit both high operational and mechanical stability; this is indicated by a bias-stress-induced threshold voltage shift (∆V _TH ≈ 4.27 V under an excessive gate bias stress of 1.7 MV cm ⁻¹ for 1 h 30 min) comparable to that of OFETs on a rigid silicon substrate, moderate field-effect mobility, and a threshold voltage stability under 1000 bending cycles with a compressive strain of 1%. The demonstration of highly stable OFETs on paper enabled by the simple planarization method will expand the potential use of various types of paper in electronic applications.