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arXiv · 1903.03062

Nanoscale Thermal Imaging of VO$_2$ via Poole-Frenkel Conduction

Alyson Spitzig·Adam Pivonka·Alex Frenzel·Jeehoon Kim·Changhyun Ko·You Zhou·Kevin O'Connor·Eric Hudson·Shriram Ramanathan·Jennifer E. Hoffman·Jason Hoffman
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Abstract

We present a method for nanoscale thermal imaging of insulating thin films using atomic force microscopy (AFM), and we demonstrate its utility on VO$_2$. We sweep the applied voltage $V$ to a conducting AFM tip in contact mode and measure the local current $I$ through the film. By fitting the $IV$ curves to a Poole-Frenkel conduction model at low $V$, we calculate the local temperature with spatial resolution better than 50 nm using only fundamental constants and known film properties. Our thermometry technique enables local temperature measurement of \textit{any} insulating film dominated by the Poole-Frenkel conduction mechanism, and can be extended to insulators that display other conduction mechanisms.

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Alyson Spitzig, Adam Pivonka, Alex Frenzel, Jeehoon Kim, Changhyun Ko, You Zhou, Kevin O'Connor, Eric Hudson, Shriram Ramanathan, Jennifer E. Hoffman, Jason Hoffman. 2022-04-13. Nanoscale Thermal Imaging of VO$_2$ via Poole-Frenkel Conduction. https://doi.org/10.1063/5.0086932

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