Growth and Photoluminescence Study of Aluminium Doped SiC Epitaxial Layers

Epitaxial layers were grown in a horizontal hot-wall CVD reactor and intentionally doped with aluminium in a wide concentration range by varying the flow of aluminium into the reactor. The layers were grown on 4H and 6H SiC substrates on both Si and C face. Low temperature photoluminescence (LTPL) has been used to characterize the layers; 6H-SiC show differences in the structure of the Al bound-exciton (Al-BE) between the two faces, suggesting that the site preference is face dependent. From the LTPL spectra the Al concentration in the layers can be estimated.