Electron beam doping was carried out at 50 and 60C on a 2-layer structure which consisted of an over-layer of Ge on a substrate of Si, and on a 3-layer structure, Si/Ge/Si. The surfaces of the overlayers were bombarded with high-energy electrons. Rutherford back-scattering spectrometric measurements of electron beam-doped samples confirmed that Ge impurity atoms were located partially in a bond-centered interstitial and in a split <111> interstitial in the Si lattice. The electron paramagnetic resonance spectrum consisted of 3 simple spectra which were attributed to a di-vacancy, a vacancy-C complex and a Si-P6 di-interstitial.

T.Wada, T.Hagino, H.Fujimoto, H.Masuda: Materials Science Forum, 1995, 196-201, 1613-8