Impact of the oxidation temperature on the density of single-photon sources formed at SiO2/SiC interface

The impact of oxidation temperature on the formation of single photon-emitting defects located at the silicon dioxide (SiO2)/silicon carbide (SiC) interface was investigated. Thermal oxidation was performed in the temperature range between 900 and 1300 C-degrees. After oxidation, two different cooling processes-cooling down in N(2 )or O-2 ambient-were adopted. Single photon emission was confirmed with second-order correlation function measurements. For the samples cooled in an N-2 ambient, the density of interface single photon sources (SPSs) increased with decreasing oxidation temperature with a density that could be controlled over the 10(5) to 10(8) cm(-2) range. For the O-2 cooled samples, on the other hand, many interface SPSs were formed irrespective of the oxidation temperature. This is attributed to the low-temperature oxidation during the cooling process after oxidation.