Identification of the Carbon Dangling Bond Center at the 4H-SiC=SiO2 Interface by an EPR Study in Oxidized Porous SiC

Jean-Louis Cantin (1) , J. von Bardeleben (1) , Y. Shishkin , Y. Ke , R. P. Devaty , W. J. Choyke

1 GPS - Groupe de Physique des Solides

We report the observation of a paramagnetic interface defect in thermally oxidized porous n-type doped 4H–SiC/SiO2. Based on its axial symmetry and resolved hyperfine interactions it is attributed to an sp3 carbon dangling bond center situated at the SiC side of the interface. This center is electrically active and pins the Fermi level in the oxidized samples. No silicon related paramagnetic dangling bond centers are observed. The formation of dangling bond centers seems to be related to interstitial oxygen diffusion at the interface during the oxidation process.

Mots clés: silicon compounds; wide band gap semiconductors; semiconductor-insulator boundaries; paramagnetic resonance; dangling bonds; interface states; Fermi level; interstitials; interface structure

Jean-Louis Cantin, J. von Bardeleben, Y. Shishkin, Y. Ke, R. P. Devaty, et al.. Identification of the Carbon Dangling Bond Center at the 4H-SiC=SiO2 Interface by an EPR Study in Oxidized Porous SiC. Physical Review Letters, 2004, 92, pp.015502. ⟨10.1103/PhysRevLett.92.015502⟩. ⟨hal-00004719⟩