Magnetic Field Sensing Based on PL6 Defects in 4H‐SiC Induced by Oxygen Ion Implantation

ABSTRACT

PL5 and PL6 defects in 4H‐polytype silicon carbide (SiC) exhibit excellent properties for quantum applications, yet their low formation yield impedes further development. Here, we combine oxygen ion implantation and subsequent thermal annealing to generate these defects in 4H‐SiC. By systematically optimizing the ion implantation and annealing conditions, we successfully fabricate high‐density defect ensembles and observe strong optically detected magnetic resonance (ODMR) signals of PL5 and PL6 defects. Focused on optimized PL6 defects, we further investigate their ODMR spectral broadening behavior as a function of laser and microwave (MW) power at room temperature and evaluate the resulting projected shot‐noise‐limited relative magnetic field sensing sensitivity. We improve the sensitivity by a factor of approximately 8 between the worst‐performing and optimum operating points in our parameter scan, with the highest sensitivity approaching 2.4 . Our findings not only provide critical insights into preparing high‐concentration modified divacancy defects in 4H‐SiC, but also deliver advances in ensemble sensing optimization and lay a foundational basis for developing high‐sensitivity SiC quantum sensors.