The migration of P in spike-doped chemical vapor deposited layers, and segregation at poly-Si/Si-substrate interfaces, were studied by means of secondary-ion mass spectroscopic and spreading resistance measurements. The time dependence of the P segregation indicated a diffusion-limited behavior; apart from a short initial period. The effect of a thin interfacial oxide upon the segregation behavior was studied by analyzing the binding energy of P atoms; segregated at the interface. This energy was compatible with values for elemental P; thus indicating that no chemical interaction with residual interfacial oxides took place. It was found that there were homogeneous charge carrier profiles across the poly-Si layer, shallow junctions (less than 50nm within the Si substrate) and steep concentration profiles with a slope of 8nm/decade at low temperatures.

D.Krüger, P.Gaworzewski, R.Kurps, J.Schlote: Semiconductor Science and Technology, 1995, 10[3], 326-31