2DTherm

The 2DTherm project tackles the ability to use Raman spectroscopy of two-dimensional materials to act as absolute nanoscale temperature probes for the development of power electronics on SiC and GaN. Indeed, current densities are such that local temperature can reach up to 350°C under certain operational conditions in these devices. Probing the local temperature is thus a crucial element as it impacts their lifetimes, degradation mechanisms and device performances. However, conventional approach by thermal simulation and infrared mapping is not sufficient as it only measures the temperature gradients. Here we propose that by using 2D materials on the device surface, very precise absolute temperatures measurements should be made possible thanks to the Raman technique (using the ratio of Stokes/Antistokes peaks or the Stokes peaks position). As a proof of concept our technique will be applied to the latest generation of power devices from STMicroelectronics. To do this, the consortium will explore the most interesting 2D materials in terms of deposition (PLD, CVD..), transfer on transistor (local buffer, pick and place, spray), Raman signature and electrical and thermal properties, and this on real bare chips and transistors in de-encapsulated plastic case. The local absolute temperature measurements will eventually allow to correct the thermal simulations, to refine the electrothermal models of the transistors to ensure the performance of the systems in a concern of reliability with cost and energy saving (dimensioning of the cooling systems) for greener electronics.