Accessible, high-resolution LCD lithography for microelectrode fabrication: Application to inkjet-printed PEDOT:PSS temperature sensors

In this work we present a cost-effective, accessible method for fabricating high-resolution patterns such as interdigitated electrodes (IDEs) using a consumer-grade Liquid Crystal Display resin (LCD) printer as an alternative to traditional photolithography. By leveraging the native 17 μm pixel high resolution of the printer's monochrome LCD and its UV source, we achieved consistent electrode structures with feature sizes down to 17 μm, without necessitating photomasks or specialized equipment. As a proof-of-concept, IDEs patterned with this method were deposited with aluminum via Direct Current (DC) magnetron sputtering and used as the base for inkjet-printed PEDOT:PSS films, creating temperature sensors optimized for monitoring human body temperature. The sensors were tested over a narrow, physiologically relevant range (36–42 °C), and exhibited a strong, voltage-tunable temperature response. Across all tested bias levels, the devices showed a clear, linear decrease in resistance with increasing temperature, with absolute temperature coefficient of resistance (TCR) values reaching as high as 159.6 ∗ 10 − 3 ° C − 1 . This performance exceeds values typically reported in literature for similar printed sensors. Overall, this approach offers a flexible, scalable, and affordable alternative to photolithography, with an emphasis on inkjet-printed temperature sensors suitable for wearable and biomedical applications. • A low-cost LCD-based lithography method achieves 17 μm resolution. • The technique enables rapid prototyping of microelectronic structures. • Inkjet-printed PEDOT:PSS sensors show strong thermal response at body temperatures. • The method provides a cost-effective approach to microfabrication.