The effect of P pre-doping upon the transient enhanced diffusion of implanted B was studied by means of secondary ion mass spectroscopy. The 40keV B ions were implanted into (100) samples to a dose of 3 x 1014/cm2. These samples had already been uniformly pre-doped with P to concentrations that ranged from 3 x 1019 to 1020/cm3. The effective B diffusivity during transient enhanced diffusion, and the fraction of immobile B, were deduced from secondary ion mass spectrometric profiles. The results showed that both of them decreased with increasing P doping level (figure 5), and saturated at a P doping level of 6 x 1019/cm3 after low-temperature annealing.

M.B.Huang, T.W.Simpson, I.V.Mitchell: Applied Physics Letters, 1997, 70[9], 1146-8