Effects of Nitrogen Impurity Concentration on Nitrogen-Vacancy Center Formation in 4H-SiC
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2020-07-28 |
| Journal | Materials science forum |
| Authors | Takuma Narahara |
Abstract
Section titled âAbstractâSpin defects of which states can be manipulated in Silicon Carbide (SiC) have drawn considerable attention because of their applications to quantum technologies. The single negatively-charged pairs of V Si and nitrogen atom (N) on an adjacent C site (N C V Si - center) in SiC is suitable for them. This paper reports the formation of N C V Si - centers on 4H-SiC epilayers with different nitrogen concentrations using light/heavy ion irradiation and subsequent thermal annealing. The formation of N C V Si - centers is characterized by the near infrared photoluminescence (PL) spectroscopy. It is shown that the PL intensity from N C V Si - centers depends on the N concentration and the ion irradiation conditions. The PL intensity increases monotonically with increasing the N concentration when the N concentration is above 2.6Ă10 16 cm -3 , whereas no linear correlation between them does not appear below that N concentration. Although the PL intensity increases with increasing defects induced by ion irradiation, the PL quenching due to neighboring residual defects appear at above the areal vacancy concentration of 10 17 vac/cm 2 and the broad Raman scattering spectra originated from vibration modes of amorphized regions hinder the PL from N C V Si - centers at above 10 18 vac/cm 2 . The formation mechanism and the charge state stability of N C V Si - centers are discussed based on the obtained results.