The room-temperature migration of vacancies into crystalline n-type material, from surface layers which had been implanted with 150keV Ge+ to doses of between 5 x 109 and 1011/cm2, was studied by monitoring the presence of E centres in the underlying layer using deep level transient spectroscopy. Under these conditions, the vacancies migrated to a maximum depth of about 1μm; and at least one vacancy per implanted Ge ion migrated into the Si crystal. The annealing of the E centres was accompanied, almost proportionately, by the appearance of a new deep level transient spectroscopy line which corresponded to a donor-like level at Ec-Et = 0.15eV. It was proposed that the center which was associated with this line was the P2-V complex. It annealed out at about 550K. A lower limit on the room-temperature diffusivity of the doubly-negative vacancy was estimated to be 4 x 10-11cm2/s.

Room-Temperature Vacancy Migration in Crystalline Si from an Ion-Implanted Surface Layer A.Nylandsted Larsen, C.Christensen, J.W.Petersen: Journal of Applied Physics, 1999, 86[9], 4861-4