Isochronal annealing studies ofn-type6H-SiC with positron lifetime spectroscopy

$n$-type 6H silicon carbide has been studied using positron lifetime spectroscopy with isochronal annealing temperatures of $400,$ 650, 900, 1200, and $1400°\mathrm{C}.$ In the as-grown sample, we have identified the $V_{\mathrm{Si}}$ vacancy, the $V_C{V}_{\mathrm{Si}}$ divacancy, and probably the $V_C$ vacancy. The silicon vacancy and the carbon vacancy were found to anneal out in the temperature range $400–650°\mathrm{C}.$ The $V_C{V}_{\mathrm{Si}}$ divacancy was found to persist at an annealing temperature of $1400°\mathrm{C}.$