We report the enhancement of the optical emission between 850 and 1400 nm of an ensemble of silicon mono-vacancies (VSi), silicon and carbon divacancies (VCVSi), and nitrogen vacancies (NCVSi) in an n-type 4H-SiC array of micropillars. The micropillars have a length of ca. 4.5 μm and a diameter of ca. 740 nm, and were implanted with H+ ions to produce an ensemble of color centers at a depth of approximately 2 μm. The samples were in part annealed at different temperatures (750 and 900 °C) to selectively produce distinct color centers. For all these color centers we saw an enhancement of the photostable fluorescence emission of at least a factor of 6 using micro-photoluminescence systems. Using custom confocal microscopy setups, we characterized the emission of VSi measuring an enhancement by up to a factor of 20, and of NCVSi with an enhancement up to a factor of 7. The experimental results are supported by finite element method simulations. Our study provides the pathway for device design and fabrication with an integrated ultra-bright ensemble of VSi and NCVSi for in vivo imaging and sensing in the infrared.

Silicon carbide (SiC) is an indirect wide band gap semiconductor that is utilized in many industrial applications due to its extreme physical properties. SiC nanoparticles (NPs) exhibit a versatile surface chemistry, fluoresce from the ultraviolet to the near‐infrared spectral ranges, and their sizes can be tuned from one to hundreds of nanometers. Yet, fluorescent SiC NPs have received far less attention by the scientific community. This review summarizes the state‐of‐the‐art in fluorescent SiC NPs. Nanoparticle fabrication methods, characterization techniques, nanoparticle surface chemistry, and SiC NPs fluorescence properties are assessed in detail. Atomic defects and impurities in the SiC crystal lattice (so‐called color centers), surface‐induced fluorescence, quantum confinement, and band‐edge fluorescence are identified as the main sources of fluorescence in SiC NPs. While many color centers are reported in bulk SiC, only few are identified in SiC NPs and interface‐related defects remain poorly understood, creating enormous potential for scientific discovery. Finally, an overview of demonstrated and emerging potential applications of SiC NPs in the areas of bioimaging and quantum sensing is provided.

The aim of this work is to study the origin of parasitic phenomena in the output characteristics of 4H-SiC MESFETs on semi-insulating (SI) substrates with various buffer layers. Ids-Vds measurements as a function of temperature have first been performed. Different parasitic effects such as kink effect, hysteresis effect when the gate voltage is successively increased or decreased, or changes in the output characteristics after a high drain polarization are presented. Random Telegraph Signal (RTS) measurements and frequency dispersion of the output conductance have next been realized. From the obtained results, we propose that the parasitic effect on the output characteristics are correlated with the presence of deep levels located near the semi -insulating substrate interface. The main observed trap is tentatively attributed to the presence of Vanadium in the SI substrate.