Electronic and optical properties of vanadium doped silicon carbide crystals grown by the sublimation sandwich method

Abstract

Cathodoluminescence-mapping experiments of n- and p-type 6H SiC intentionally doped with vanadium (V) show a local anti-correlation of the V/sup 4+/ related IR-luminescence and the near bandedge donor-acceptor pair luminescence (N/spl rarr/Al). This fact indicates, that V acts as minority carrier lifetime determining impurity. The suppression of the V/sup 4+/ luminescence near crystallographic defects is discussed under the possible mechanism of V precipitate formation. The binding-energy of the V/sup 4+/5+/ donor level is determined to E/sub v/+1.57/spl plusmn/0.05 eV by photoluminescence excitation measurements.