Prominent luminescence of silicon-vacancy defects created in bulk silicon carbide p-n junction diodes

We investigate fluorescent defect centers in 4H silicon carbide p-n junction diodes fabricated via aluminum-ion implantation into an n-type bulk substrate without the use of an epitaxial growth process. At room temperature, electron-irradiated p-n junction diodes exhibit electroluminescence originating from silicon-vacancy defects. For a diode exposed to an electron dose of 1x1018 cm-2 at 800 keV, the electroluminescence intensity of these defects is most prominent within a wavelength range of 400-1100 nm. The commonly observed D1 emission was sufficiently suppressed in the electroluminescence spectra of all the fabricated diodes, while it was detected in the photoluminescence measurements. The photoluminescence spectra also displayed emission lines from silicon-vacancy defects.