SPIN COATING FILM FORMING DEVICE

PROBLEM TO BE SOLVED: To make it possible to directly monitor the mists above a wafer and to manage the adhesion of dust to a coating film during a film forming stage by providing a spin coating film forming device constituted to drop a liquid material into the wafer attracted onto a spin chuck with an optical mist measuring means above the wafer. SOLUTION: At the time of forming the film of a resist or SOG(spin on glass) film, etc., the mist of the atmosphere above the wafer W is first measured by the mist measuring means 10 consisting of a light transmitting part 9a and a light receiving part 9b. Namely, the dust adhesion to the coating film formed on the wafer W is monitored in real time during the film formation. Whether or not this measured value is within the range of a preset permissible set value is judged and if this value is within the permissible set value, spin coating is executed by dropping the resist or SOG, etc., from a coating nozzle 7 of a material supplying means 3 onto the wafer W fixed on the spin chuck 2 by vacuum suction into the spin chuck 2. If, on the other had, the measured value is off the range of the measured permissible value, an alarm is emitted and the film formation of the coating film is stopped.