“…2͒ but electrically inactive defects, such as clusters, form if the heat treatment is extended. 3 The existence of C-C pairs in annealed epilayers was later demonstrated by Raman scattering measurements made on GaAs samples that contained both 12 C and 13 C isotopes: two triplet structures (T1 and T2) were observed, which were attributed to different C-C complexes. 4 Consistent with these observations, this study also revealed a loss of substitutional carbon.…”