A model of boron incorporation into a silicon epitaxial film is experimentally and theoretically studied in a B2H6-SiHCl3-H-2 system at atmospheric pressure. The boron concentration in the silicon epitaxial film is evaluated using the ratio of the boron deposition rate to the total deposition rate of boron and silicon, both of which are calculated accounting for the entire transport phenomena in the horizontal cold-wall single-wafer epitaxial reactor having a rotating susceptor and substrate. The overall rate constant for the surface reaction of B2H6 gas is found to be a function of the surface coverage of the silicon substrate surface due to the chemisorption of SiHCl2 gas. The practical application for adjusting the carrier concentration profile using the combination of the substrate rotation and the inlet of the reactor is also discussed.