High‐Performance, Paper‐Based Microelectronics via a Micromodular Fabrication Process

ABSTRACT The integration of high‐performance microelectronics onto flexible, sustainable substrates is important for advancing eco‐friendly technologies. This study presents an approach for creating circuits comprised of silicon micromodular transistors on cellulose nanomaterial (CNM)‐coated paper substrates with silver nanoparticle interconnects formed using electrohydrodynamic jet (e‐jet) printing. The transistors exhibit on/off ratios of ∼10 ⁷ , threshold voltages of 0.00 ± 0.06 V, subthreshold slopes of 102 ± 5 mV/decade, and peak effective mobilities of 430 ± 60 cm ² V ⁻¹ s ⁻¹ . Cellulose nanofibril (CNF) and cellulose nanocrystal (CNC) coatings are evaluated for mechanical and electrical performance. CNF‐based coatings offer lower reverse saturation current despite higher surface roughness, while smoother CNC‐based coatings exhibit higher reverse saturation current. Wired micromodular transistors maintain performance under radii of curvature bending strain as small as 2.3 mm. A depletion‐load inverter serves as proof‐of‐concept micromodular circuitry. To the best of our knowledge, this work demonstrates a circuit assembly technique on paper that mitigates many of the trade‐offs of previous paper‐based platforms.