The growth of a displacement field in monocrystalline material, resulting from high-dose H implantation and subsequent heat treatment, was investigated by means of MeV He Rutherford back-scattering under channelling conditions, double-crystal X-ray diffraction, and transmission electron microscopy. The results which were obtained for samples that had been annealed for various times at temperatures ranging from 220 to 350C were explained in terms of a kinetic model which assumed the formation of clusters of H molecules. The growth of the displacement field was thermally activated, with an activation energy of 0.50eV; thus suggesting that the limiting process might be the release of H atoms bound to the defects which were created by ion implantation.

D.Bisero, F.Corni, S.Frabboni, R.Tonini, G.Ottaviani, R.Balboni: Journal of Applied Physics, 1998, 83[8], 4106-10