The influence of the technological parameters of deposition, the purity and relative concentration of diborane, and the substrate temperature on electrical parameters of (a-Si:H):B films obtained by high-frequency decomposition of a gaseous mixture in a multielectrode system was studied. Simultaneous existence of the mechanisms for doping and modification in the case of introduction of boron from diborane in the course of deposition of (a-Si:H):B films is proposed.