Method and apparatus for treating film coated on substrate

A film treating method for treating a resist film which is formed on a substrate by spin coating, comprising:

• a step of coating a resist composition containing a solvent on the substrate to form the resist film;
• a step of mounting the substrate coated with the resist film on a mount table;
• a step of covering the substrate coated with the resist film with a cover so as to define a sealed small-volume space, whereby an atmosphere of a saturated vapor or a super-saturated vapor of the solvent is formed in said sealed small-volume space before solvent included in the resist film is lost;
• a step of executing a first heating process in said sealed space wherein the substrate coated with the resist film is heated at a temperature which lowers the viscosity of the resist film and permits solvent to remain in the resist film in an amount sufficient to maintain the fluidity of the resist film;
• a step of removing the cover so as to change said sealed small-volume space to a non-sealed space surrounding the substrate coated with the resist film;
• and
• a step of executing a second heating process in said non-sealed space wherein the substrate coated with the resist film is heated at a temperature higher than that of the first heating process, thereby permitting the solvent to evaporate from the resist film.