PURPOSE: To secure practically necessary precision and to obtain a result in a short time by determining the attribute of a particle of a base solid phase and determining the behavior according to the substrate phase particle on which a vapor phase particle sticks.

CONSTITUTION: The position of a collision between the vapor phase particle and solid phase is calculated to determine the kind of the colliding solid phase (2). Then it is judged whether or not the vapor phase particle and solid phase particle cause surface reaction (3). At this time, the case wherein the surface reaction between the vapor phase particle and solid phase particle is possibly caused due to the flight of the vapor phase particle is one of a case wherein a reaction product is generated and only sticks on the surface (61), a case wherein only the vapor phase particle is generated as the reaction product (62), a case wherein the reaction products are vapor and sticking matter (63), and a case wherein nothing is produced (64). Then simulation is performed respectively in consideration of the possibility that the vapor phase particle sticks on a solid phase substrate or a particle sticking on the substrate, the possibility that the vapor phase particle causes a chemical reaction on the substrate, and the possibility that the sticking vapor phase particle is decomposed after sticking.