Processing-dependent Thermal Response of Nanostructured Platinum Thin Films Fabricated via Spark Ablation

In this work, we report a simple, scalable, and dry fabrication technique for realizing thin-film platinum resistance temperature detectors (RTDs), utilizing spark ablation technology. Pure spark-ablated platinum nanoparticles, with an average diameter of around 2.2 nm, were directly deposited through chemical-free impaction printing onto the substrate, enabling direct sensor patterning without complex processing steps. Experimental investigations revealed that higher deposition speeds produce sparser and thermally unstable films, with 1 mm/min identified as the optimal printing rate. Additionally, it was established that the film temperature coefficient of resistance (TCR) improves with increasing layer thickness, achieving a maximum mean TCR of 2.17 × 10−3°C−1 for an 8-layer RTD. The printed Pt sensor demonstrated linear temperature-resistance characteristics while maintaining high stability and repeatability over multiple thermal cycles, spanning 25–200 °C. This study lays the groundwork for advancing practical and cost-effective printed thermal sensing technologies.