A thin film of a uniform film thickness is formed even without increasing the film deposition rate. The temperature of an evaporation device disposed in an evaporation chamber is raised in advance, and an organic material is dropped from a supply unit onto an evaporation surface of the evaporation device; and when the organic material is evaporated, a heated carrier gas is introduced into the evaporation chamber, and is mixed in the evaporation chamber and is introduced into a discharger. While a molecular flow is formed in the discharger in a case that only the organic material vapor is introduced into the discharger, the pressure within the discharger is raised due to the carrier gas, so that a viscous flow is formed and the mixed gas is filled in the discharger and is uniformly discharged. The organic material may be supplied by a small amount and the film deposition rate may not become too high.