Annealing behaviour of In impurities in SiC after ion implantation

Abstract

The annealing behaviour of indium impurities in SiC after ion implantation, and the formation and stability of complexes at In in SiC have been studied by perturbed angular correlation (PAC) spectroscopy for the first time. Samples of 6H-SiC and 3C-SiC single crystals were doped with radioactive 111In by ion implantation. The implantation-induced radiation damage was annealed by furnace treatment up to 1250K. In the 6H-modification two different electric field gradients (EFG) characterized by the quadrupole coupling constants v Q1 = 36(1) MHz, v Q2 = 63(2) MHz and asymmetry parameters η 1 = 0.00 (10), η 2 = 0.65 (10), respectively, were observed. The EFG 1 is assigned to the lattice EFG experienced by the probe atoms at carbon sublattice sites. The EFG 2 indicates the formation of a distinct In-defect complex, which vanishes at temperatures above 320 K. In the 3C-modification no distinct EFG could be detected.