The influence of antimony addition on the temperature of the silicon melt surface was studied. It was found that the temperature of the silicon melt surface in a quartz crucible decreased due to evaporation of antimony oxide. This tendency was more pronounced under low pressure in the chamber. In the cases of less amount of antimony addition, the temperature variations were ambiguous. An approximate estimate for the latent heat of evaporation of species from the silicon melt surface was carried out based on our experimental results. The preliminary estimated result for the latent heat of evaporation of species was in the range of 110 to 170 kJ/mol.