Silicon technology is more than 80 years old, and today large technological plants manufacture complex electronic circuits at the submicron scale. Going beyond the semiconductor property of silicon circuits to naturally include superconducting elements, would open extremely interesting fields of application for space observation. 

We know today  that silicon heavily doped around 8% with Boron becomes a superconductor, as discovered by CNRS labs in 2006. Its high resistivity above the Tc will allow the coexistence of semi-conductive and superconductive functions. Today within CEA/LETI we know how to perform doping by femtosecond laser-assisted implantation, which reduces the size of patterns at the micron scale. Nevertheless, the fundamental properties of the material at these scales are poorly known. This PhD is a prerequisite for the realization of new sub-Kelvin detectors, for X-ray or infrared and millimetric spectroscopy (KIDs, bolometers).

The experimental team test and uses already superconducting layers for more than twenty years for ancillary functions in the detectors (light absorption,...). Today superconducting sensors show a wide domain of applications at cryogenic temperature. 

The PhD described here is ment to complete the CNES R&T demand called SuSi_Car. It gives, to the candidate, the opportunity to participate in a complete development from one of the largest technological plants in Europe  (MINATEC) to the DAp cryogenic test facility in Paris-Saclay University.

The characterization of superconducting Silicon is made in a wide collaboration between CNRS laboratories (I Neel, C2N,...) and CEA.

=================

For more Information about the topics and the co-financial partner (found by the lab!); contact Directeur de thèse - laurent.dussopt@cea.fr

Then, prepare a resume, a recent transcript and a reference letter from your M2 supervisor/ engineering school director and you will be ready to apply online before March 13th, 2026 Midnight Paris time!