Investigation of microstructure and photoluminescence of Mn and Co co-doped SiC films

Mn and Co co-doped SiC films were fabricated on Si (1 0 0) substrates by RF-magnetron sputtering. The lattice structure, composition, chemical valences and photoluminescence of the films were investigated. The lattice structure analysis shows that the films are composed of 3C-SiC and the doped Co atoms form CoSi secondary phase compounds in the films. The analyses of composition and valences display that the doped Mn and Co atoms are in the form of Mn2+ and Co2+ in the films, respectively. The analysis of local structure reveals that the doped Mn substitute for C sites in SiC lattice and no Co or Mn clusters, and Mn- and Co-related compounds except CoSi appear in the films. A violet peak located at 413 nm for all the films can be observed in photoluminescence spectra, and the peaks become stronger with the increase of Mn concentration, which should be associated with C clusters.