Noncontact thermometry based on direct electron detection of electron-backscattering diffraction patterns

Accurate temperature measurement at the nanoscale is crucial for thermal management in next-generation microelectronic devices. Existing optical and scanning-probe thermometry techniques face limitations in spatial resolution, accuracy, or invasiveness. In this work, we demonstrate a fast and noncontact nanothermometry method based on temperature-induced changes in electron backscattering diffraction (EBSD) patterns captured by a high-performance direct electron detector within a scanning electron microscope (SEM). Using dynamical electron simulations, we establish the theoretical temperature sensitivity limits for several semiconductors ($\mathrm{Si}$, $\mathrm{Ge}$, $\mathrm{Ga}\mathrm{As}$, and $\mathrm{Ga}\mathrm{N}$), showing that thermal diffuse scattering leads to a measurable smearing of Kikuchi bands in the EBSD patterns. We develop a Fourier analysis method that captures these subtle changes across the full diffraction pattern, achieving a simulated temperature sensitivity of approximately 0.15% per K. Experimental results on silicon confirm a sensitivity of 0.14% per K and achieve a 13-K temperature uncertainty with a 10-s acquisition time, and enable spatial temperature measurement under thermal gradients. Our approach offers a pathway toward practical and high-resolution thermal measurement directly in SEMs, expanding the toolbox for device-level thermal diagnostics.