PURPOSE: To enable a high-grade thin film to be formed at low temperature by supplying a reaction gas into space formed by a substrate holder and the adjacent auxiliary electrode.

CONSTITUTION: Plasma is formed by glow discharge between a holder 2 and an electrode 4 while reaction gas is being supplied to a relatively narrow space 3 which the substrate holder 2 where the substrate 3 within a vacuum room 1 is mounted and the auxiliary electrode 4 provided at the outer periphery of the gas discharge port 4a surrounding the substrate 3. Then, if an evaporation object 6 of an evaporation source 5 is evaporated and a shutter 9 is opened, the substrate 3 is not heated, reaction between plasma and the evaporation object progresses, and an improved thin film can be formed at low temperature.