Thermal Sensors on Cellulose Based Substrate for Green Thin-Film Electronics

Sustainable leveraging of natural resources is imperative to move toward next-generation electronics, balancing functionality, affordability, and sustainability. In this perspective, the use of sustainable materials is an effective way to combine electronics development and low carbon footprint. Here, we successfully introduced thin-film resistance temperature detectors (RTDs) and thin-film thermistor sensors on a triacetyl cellulose (TAC) film derived from sustainable plant-based cellulose. These devices are tested in a temperature range of 25° C to 75° C, demonstrating average sensitivity of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$0.21 \%{ }^{\circ} \mathbf{C}^{-1}$</tex> for the RTDs, and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$0.26 \%{ }^{\circ} \mathrm{C}^{-1}$</tex> for the thermistors. Device performances are demonstrated while mechanical strain is applied, with reliable functionality down to 8 mm bending radii. Finally, device dissolution in deionized water revealed the transient nature of the thermistor sensor after 10 days. These results demonstrate the potential of a cellulose based substrate and its integration with thin-film devices for the realization of green and yet sustainable electronics.