Patent ID: 7506457

Claim:
A substrate treating apparatus for drying substrates by moving the substrates out of a treating liquid into a solvent atmosphere, comprising: a treating tank for storing the treating liquid; a chamber enclosing said treating tank; a holding mechanism for holding the substrates, said holding mechanism being vertically movable between a treating position in said treating tank and a drying position in said chamber and above said treating tank; a supply device for supplying vapor of a solvent into said chamber; a buffer tank disposed outside said chamber for collecting the treating liquid discharged from said treating tank; a first decompressing device for decompressing said chamber; a second decompressing device for decompressing said buffer tank; and a control device for operating said supply device to fill said chamber with the solvent atmosphere, operating said holding mechanism to move the substrates from the treating position to the drying position, operating said first decompressing device to decompress said chamber to a first pressure, and operating said second decompressing device to adjust a pressure in said buffer tank to a second pressure equal to or lower than said first pressure before the treating liquid in said treating tank is discharged into said buffer tank.