Abstract: The object of the present invention is to provide a microstructure drying treatment method by which a substrate having a microstructure has a fine pattern of less than 30 nm and a large-caliber substrate of 100 mm or more can be dried uniformly and in a short time without generating pattern collapse, and its apparatus and its high pressure vessel. The present invention is a microstructure drying treatment method of introducing a fluid that is gas at normal temperature and pressure and is liquid under high pressure inside a high pressure vessel in which a substrate having a microstructure in a state immersed in or wet with a rinsing liquid in a liquid or supercritical state. The method forms a specific gravity difference between the rinsing liquid and fluid inside the high pressure vessel and collects the rinsing liquid to the upper side or lower side of the high pressure vessel by changing at least one side of the temperature and pressure of the fluid and changing the specific gravity of the fluid.

Abstract: The object of the present invention is to provide a microstructure drying treatment method by which a substrate having a microstructure has a fine pattern of less than 30 nm and a large-caliber substrate of 100 mm or more can be dried uniformly and in a short time without generating pattern collapse, and its apparatus and its high pressure vessel. The present invention is a microstructure drying treatment method of introducing a fluid that is gas at normal temperature and pressure and is liquid under high pressure inside a high pressure vessel in which a substrate having a microstructure in a state immersed in or wet with a rinsing liquid in a liquid or supercritical state. The method forms a specific gravity difference between the rinsing liquid and fluid inside the high pressure vessel and collects the rinsing liquid to the upper side or lower side of the high pressure vessel by changing at least one side of the temperature and pressure of the fluid and changing the specific gravity of the fluid.