Nuclear reaction analysis using the 12C(d,p)13C reaction, together with Rutherford back-scattering spectrometry in the channelling geometry, was used to evaluate the substitutional fraction of C in (100)-oriented semi-insulating material which had been implanted with 12C ions to a dose of 5 x 1016/cm2. The substitutional fraction of implanted C, as evaluated by means of nuclear reaction analysis, was equal to 19% in samples which were annealed at 600C. The electrical activation rate of the same sample was equal to 2.1%, when measured by using the van der Pauw method. It was suggested that possible sources of this discrepancy were compensating centers such as the As vacancy, VAs, and/or VAs-CAs complexes which were introduced during annealing. This suggestion was supported by the surface precipitation of As, observed by means of Raman scattering, and by the enhancement of the surface peak in the Rutherford back-scattering spectroscopic channelling yield.

Relationship between the substitutional fraction and electrical activation of carbon in heavily C ion-implanted GaAs K.Kuriyama, T.Koyama, K.Kushida, N.Hayashi, N.Kobayashi, M.Hasegawa: Journal of Applied Physics, 1999, 85[9], 6926-8