ON THE MECHANISM OF BORON INCORPORATION DURING SILICON EPITAXY BY MEANS OF CHEMICAL-VAPOR-DEPOSITION

A careful re-examination of experimental results on in situ boron-dopi ng during silicon epitaxy which have been previously published(16) per mits us to discuss how boron adsorption rate, desorption, and incorpor ation rate are dependent on silicon growth rate. It is shown for the f irst time that boron incorporation covers the whole range from equilib rium-limited to kinetically controlled incorporation when certain depo sition conditions are met. In the transition region boron incorporatio n is affected by the reduction of boron adsorption not only due to the consumption of adsorbed boron species by the doping process but also by the increasing hindrance of boron adsorption due to the increase in the film growth rate. At other deposition conditions the known adsorp tion-desorption model of silicon doping describes boron incorporation completely.