Thermo-tomography of buried interfaces in micro-supercapacitors – TTIMSCAP

Heat is one of the main challenges in electronics, further exacerbated by continuous component miniaturization and higher power densities. The integration of multiple components on a single chip with the rise of connected and autonomous devices intensifies heat dissipation requirements, as well as on-chip energy production and storage needs. Whereas batteries are currently the main storage solutions in such devices, supercapacitors offer a promising alternative in some scenarios. Although their performance and longevity are impacted by temperature, the thermal properties are usually only estimated from models and it is therefore crucial to characterize the thermal properties from the nanoscale of the materials to the device scale.
The TTIMSCAP project aims to develop an original thermal measurement system to access the 3D time-dependent temperature field within a heterogeneous and multiscale device and apply the technique to the study of in-operando on-chip micro-supercapacitors. The measurement system will combine confocal microscopy with infrared thermo-tomography and use fast pulsed lasers with a heterodyne scheme to access all relevant temporal scales. Inversion methods will be used to extract thermal diffusivities from the temperature field reconstructed with super-resolution algorithms. More importantly, the thermal contact resistance of buried interfaces will be measured, as interfaces are often thermal bottlenecks. The measurements will allow us to provide guidelines for the design of more efficient micro-supercapacitors and identify thermal management strategies. The double originality of the project of combining an innovative multiscale thermal measurement system and its use on operating micro-supercapacitors will also impact other scientific fields for which thermal properties within devices or biological tissues are of interest.