Mechanically detected terahertz electron spin resonance using SOI-based thin piezoresistive microcantilevers

[Display omitted] •Novel fabrication process of piezoresistive cantilevers based on SOI wafers and spin-on diffusion.•Thin customized piezoresistive cantilevers with a built-in compensation circuit.•Piezoresistive detection of multi-frequency ESR spectroscopy for 80–160 GHz. We developed piezoresistive microcantilevers for mechanically detected electron spin resonance (ESR) in the millimeter-wave region. In this article, fabrication process and device characterization of our self-sensing microcantilevers are presented. High-frequency ESR measurements of a microcrystal of paramagnetic sample is also demonstrated at multiple frequencies up to 160 GHz at liquid helium temperature. Our fabrication is based on relatively simplified processes with silicon-on-insulator (SOI) wafers and spin-on diffusion doping, thus enabling cost-effective and time-saving cantilever fabrication.