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Achieving high precision in the fabrication of electronic circuits through additive manufacturing requires breaking the resolution limit of traditional printing processes. To address this challenge, we have developed a novel approach that involves preparing a heterogeneous wetting surface using a light-sensitive NBE-acrylate resin. By creating differences in surface energy on the substrate, we can limit the spread of the ink and surpass the limitations of conventional processes, achieving a printing resolution of 5 μm. The NBE-acrylate resin can be cross-linked under white LED light illumination (with λ > 400 nm) to yield a hydrophobic surface, which can be converted to a hydrophilic surface by UV light illumination (λ = 254 nm). The photochemical reaction of the NBE-acrylate resin under different light irradiation was confirmed by FTIR and AFM microforce measurements. In combination with a photomask, patterned heterogeneous wettability surfaces were prepared, which can be utilized for printing precision electronic circuits. Micrometer-scale printed circuits with a low line-to-space (L/S) of 5/50 and 10/10 μm were successfully achieved by optimizing the ink formulation, which is significantly beyond the printing resolution. In the end, fully printed thin film transistor arrays based on semi-conducting carbon nanotubes were achieved, which showed higher charge carrier mobilities of 1.89-4.31 cm2 s-1 V-1 depending on the channel width, demonstrating the application of this precision printed technique.
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