Patent ID: 8015984

Claim:
A substrate processing apparatus for processing a single substrate having a predetermined circuit pattern formed thereon by photolithography, the apparatus comprising: a holder that horizontally holds and rotates the single substrate; a liquid processing mechanism that performs liquid processing by bringing purified water into contact with a surface of the substrate, the liquid processing mechanism including a liquid processing nozzle that supplies the purified water onto the substrate held on the holder and is movable to scan over the substrate; a drying mechanism that supplies a fluid mixture consisting essentially of purified water and a volatile organic solvent to the surface of the substrate in order to dry the substrate, the drying mechanism including a drying nozzle that supplies the fluid mixture onto the substrate held on the holder and is movable to scan over the substrate, wherein the drying mechanism includes a mixing portion that mixes the purified water and the volatile organic solvent to prepare the fluid mixture, a first flow regulator that adjusts a flow rate of the purified water supplied to the mixing portion, and a second flow regulator that adjusts a flow rate of the volatile organic solvent supplied to the mixing portion, and wherein the apparatus further comprises a ratio controller that controls one or both of the first and second flow regulators such that a ratio of a concentration of the volatile organic solvent relative to a concentration of the purified water, in the fluid mixture supplied from the mixing portion to the substrate, continuously or gradually rises with time.