In one embodiment, after rinsing a semiconductor substrate having a fine pattern formed thereon with pure water, the pure water staying on the semiconductor substrate is substituted with a water soluble organic solvent, and then, the semiconductor substrate is introduced into a chamber in a state wet with the water soluble organic solvent. Then, the water soluble organic solvent is turned into a supercritical state by increasing a temperature inside of the chamber. Thereafter, the inside of the chamber is reduced in pressure while keeping the inside of the chamber at a temperature enough not to liquefy the pure water (i.e., rinsing pure water mixed into the water soluble organic solvent), and further, the water soluble organic solvent in the supercritical state is changed into a gaseous state, to be discharged from the chamber, so that the semiconductor substrate is dried.