Substrate processing method, substrate processing apparatus and pre-drying processing liquid
A pre-drying processing liquid containing a sublimable substance that changes to gas without passing through to a liquid and a solvent in which the sublimable substance dissolves is supplied to a front surface of a substrate on which a pattern has been formed. Thereafter, the solvent is evaporated from the pre-drying processing liquid on the front surface of the substrate to thereby form a solidified body containing the sublimable substance on the front surface of the substrate. Thereafter, the solidified body is sublimated and thereby removed from the front surface of the substrate. A value acquired by multiplying a ratio of the thickness of the solidified body to the height of the pattern by 100 is greater than 76 and less than 219.
1. A substrate processing method comprising:
a pre-drying processing liquid supplying step of supplying a front surface of a substrate, on which a pattern has been formed, with a pre-drying processing liquid containing a sublimable substance that changes to gas without passing through to a liquid and a solvent in which the sublimable substance dissolves;
a film thickness reducing step of reducing a film thickness of the pre-drying processing liquid on the substrate while maintaining a state in which an entire front surface of the substrate is covered with a liquid film of the pre-drying processing liquid by rotating the substrate at a film thickness reducing speed to remove some of the pre-drying processing liquid on the front surface of the substrate until the film thickness is stabilized at a value corresponding to the film thickness reducing speed;
a solidified body forming step of forming a solidified body containing the sublimable substance on the front surface of the substrate by evaporating the solvent from the pre-drying processing liquid on the front surface of the substrate and gradually increasing a concentration of the sublimable substance in the pre-drying processing liquid and gradually reducing the film thickness of the pre-drying processing liquid; and
a sublimating step of removing the solidified body from the front surface of the substrate by sublimating the solidified body, wherein
the concentration of the sublimable substance in the pre-drying processing liquid that has not yet been supplied to the substrate is adjusted such that a value acquired by multiplying a ratio of a thickness of the solidified body when the solidified body is formed to a height of the pattern by 100 is 102 or greater and 138 or less, while controlling that a mass percent concentration of the sublimable substance in the pre-drying processing liquid is 0.89 or greater and 1.24 or less and a thickness of the solidified body is 100 nm or greater and 200 nm or less.