Point Defects in Chemical-Vapor Deposited Diamond, High-Purity Semi-Insulating SiC, and Epitaxial GaN

Abstract

The native and impurity induced point defects in undoped chemical-vapor deposited diamond, high-purity semi-insulating SiC and grown by molecular beam epitaxy GaN were investigated by isothermal charge-based deep level transient spectroscopy (Q-DLTS). It was found that deep levels in undoped diamond have a continuous energy spectrum with two maximums at energies 0.71 and 0.54 eV. Several discrete deep levels were found in SiC. Defect level E1 is attributed to atom displacement on the carbon sublattice in SiC. Levels E2, E4 are related to (Vc -Vsi) complex and silicon vacancy Vsi, respectively. Obtained values of activetion energy and capture cross-section allow expecting that deep level E3 associated with the carbon vacancy Vc, while acceptor level En is vanadium-induced level. Eight deep levels were observed in GaN. Levels E1, E2, E7, and E8 have been observed in low doped n-GaN are characterized for the first time in our studies.