Seeing Through Materials: Mapping the Hidden Electrical World at the Nanoscale with the Scanning Microwave Microscopy
How do we measure the conductivity of a single nanowire or the dielectric constant of a 2D material without damaging it? While standard Atomic Force Microscopy (AFM) provides surface information by “touching” a sample, Scanning Microwave Microscopy (SMM) allows us to sense how materials respond to high-frequency electromagnetic fields, using the same technology found in your smartphone.
This seminar bridges the gap between mechanical probing and microwave sensing. We will begin with a brief journey through the fundamentals of Scanning Probe Microscopy (AFM and Scanning Tunneling Microscopy, or STM), highlighting their strengths and their inherent limitations. We will then introduce SMM and discuss how it can be used to obtain quantitative measurements. Finally, we will explore a novel “Inverted” approach (iSMM), which literally turns the technique upside-down. By illuminating thin-film samples from below through a transmission line, iSMM overcomes the sensitivity barriers and practical limits of traditional setups. This breakthrough allows us to map permittivity and conductivity with unprecedented precision, providing a new lens through which to study 2D materials, semiconductors, and nanostructures.
Bio: Marco Farina received the “laurea” degree and the Ph.D. in electronic engineering from the UniversitÃÂ di Ancona (Italy); he has been a professor of electromagnetics at the UniversitÃÂ Politecnica delle Marche (Italy) since 1999, achieving the rank of full professor in 2013. He is Mary J. Upson Visiting Professor at Cornell University since July 2025.
Farina is the author of the electromagnetic modeling software EM3DS (Electromagnetic 3D Silmulator), developed between 2000 and 2019, which is utilized by several institutions, laboratories, and companies for research and design. He co-authored the book “Advanced electromagnetic analysis of passive and active planar structures” (IET, 1999) and has published over 200 papers and conference proceedings; he was awarded several patents for calibration techniques, microscopy and sensors. His contributions appear in several high-impact, interdisciplinary, and physics journals such as Nature Communications, Applied Physics Letters, Nanoscale, Small, and IEEE Transactions on Microwave Theory and Techniques, among others.