Studies of the effect of C upon the formation of thermal donors, during the annealing of oxygenated crystals at temperatures of between 400 and 800C, revealed that the presence of large concentrations of C (comparable to the O content of 8 x 1017/cm3) resulted mainly in the formation of singly-charged thermal donors. These had thermal ionization energies of 0.024 to 0.038eV and g-factors of between 1.9985 and 1.9993; and a large fraction of them was stable against annealing at higher temperatures. Neither ordinary doubly-charged thermal donors nor thermal acceptors such as Si-N K-centers formed in these crystals.

V.M.Babich, N.P.Baran, A.A.Bugai, V.I.Kiritsa, V.M.Maksimenko: Fizika i Tekhnika Poluprovodnikov, 1996, 30[5], 777-82 (Semiconductors, 1996, 30[5], 417-9)