Substrate processing method and substrate processing apparatus
A substrate processing method of the invention includes: a first step of introducing a processing fluid in a gas phase into a chamber housing a substrate; a second step of changing the processing fluid in the chamber from the gas phase to a supercritical state without intervention of a liquid phase; a third step of changing the processing fluid in the chamber from the supercritical state to a liquid phase; a fourth step of changing the processing fluid in the chamber from the liquid phase to a supercritical state; and a fifth step of changing the processing fluid in the chamber from the supercritical state to a gas phase without intervention of a liquid phase and discharging the processing fluid from the chamber.
1 . A substrate processing method for drying a substrate by replacing a liquid adhering to the substrate with a processing fluid in a supercritical state, the substrate processing method comprising:
introducing the processing fluid in a gas phase into a chamber housing the substrate;
after introducing the processing fluid in the gas phase into the chamber housing the substrate, changing the processing fluid in the chamber from the gas phase to a supercritical state without intervention of a liquid phase;
after changing the processing fluid in the chamber from the gas phase to the supercritical state without intervention of the liquid phase, changing the processing fluid in the chamber from the supercritical state to a liquid phase;
after changing the processing fluid in the chamber from the supercritical state to the liquid phase, changing the processing fluid in the chamber from the liquid phase to the supercritical state; and
after changing the processing fluid in the chamber from the liquid phase to the supercritical state, changing the processing fluid that was changed from the liquid phase to the supercritical state in the chamber from the supercritical state to the gas phase without intervention of a liquid phase and discharging the processing fluid from the chamber.
2 . The substrate processing method according to claim 1 , wherein in changing the processing fluid from the gas phase to the supercritical state, the processing fluid lower in temperature than a critical temperature of the processing fluid is brought into the supercritical state by being adiabatically compressed.
3 . The substrate processing method according to claim 2 , wherein in introducing the processing fluid into the chamber, the processing fluid in the gas phase lower in temperature than a critical temperature of the processing fluid is introduced into the chamber.
4 . The substrate processing method according to claim 1 , wherein in changing the processing fluid from the gas phase to the supercritical state, pressure of the processing fluid higher in temperature than a critical temperature of the processing fluid is increased to be equal to or greater than a critical pressure to bring the processing fluid into the supercritical state.
5 . The substrate processing method according to claim 1 , wherein in changing the processing fluid from the supercritical state to the liquid phase, the processing fluid in the liquid phase is supplied from outside into the chamber filled with the processing fluid in the supercritical state.
6 . The substrate processing method according to claim 5 , wherein in changing the processing fluid from the supercritical state to the liquid phase, the processing fluid in the liquid phase supplied into the chamber is discharged at least partially from the chamber.
7 . The substrate processing method according claim 1 , wherein in changing the processing fluid from the liquid phase to the supercritical state, the processing fluid in the chamber is changed from the liquid phase to the supercritical state by increasing temperature of the processing fluid.
8 . The substrate processing method according to claim 1 , wherein in changing the processing fluid from the supercritical state to the gas phase, pressure of the processing fluid is reduced to be equal to or less than a critical pressure while the processing fluid is maintained at a temperature equal to or greater than a critical temperature.
9 . The substrate processing method according claim 1 , wherein the liquid is an organic solvent and the processing fluid is carbon dioxide.
10 . A substrate processing apparatus to perform drying a substrate by replacing a liquid adhering to the substrate with a processing fluid in a supercritical state, the substrate processing apparatus comprising:
a chamber which houses a substrate;
a fluid supplier which is capable supplying a processing fluid in a gas phase and a high-pressure processing fluid that is the processing fluid at a higher pressure than a critical pressure of the processing fluid to the chamber;
a pipe through which the high-pressure processing fluid is passed from the fluid supplier to the chamber;
a buffer which is interposed in the pipe and in which the high-pressure processing fluid output from the fluid supplier is stored temporarily;
an open/close part which is interposed in the pipe between the buffer and the chamber and which opens and closes a flow passage of the high-pressure processing fluid from the buffer to the chamber; and
a controller which controls the fluid supplier and the open/close part, wherein the controller is configured to execute the substrate processing method according to claim 1 .
11 . The substrate processing apparatus according to claim 10 , further comprising a heater which is interposed between the buffer and the open/close part and heats the high-pressure processing fluid to a temperature equal to or greater than a critical temperature.