Two kinds of sample were used, one of which contained a sequence of B spikes and one of which had a sequence of alternating B and Sb spikes. Both were grown by means of molecular beam epitaxy. The samples were bombarded with 2.5MeV protons, at 500 to 830C, and were characterized by using secondary ion mass spectrometry. The energy of the proton beam was chosen so that the generation rate of point defects could be considered to be uniform throughout the δ-doped samples. The effects of the sample surface and of the B concentration (5 x 1015 to 3.2 x 1018/cm3) upon B diffusion were studied in detail. For each sample, the B diffusion coefficient increased under irradiation; as compared with the B diffusion coefficient in non-irradiated areas. This enhancement depended upon the irradiation temperature, upon the position of the B spike and upon the B concentration. The presence of Sb enhanced B diffusion during low-temperature proton bombardment.

Irradiation Enhanced Diffusion of Boron in Delta-Doped Silicon. P.Leveque, A.Y.Kuznetsov, J.S.Christensen, B.G.Svensson, A.Nylandsted Larsen: Journal of Applied Physics, 2001, 89[10], 5400-5