Substrate treating apparatus and substrate treating method

A substrate treating apparatus for treating a substrate, comprising:

• a substrate treating unit configured to supply a water-insoluble water repellent to the substrate to perform water-repellent treatment to the substrate;
• a decomposition solution mixing mechanism configured to mix a decomposition solution for decomposing the water repellent to a water repellent-containing liquid that contains the water repellent as a waste liquid generated through the water-repellent treatment;
• and
• a discharging unit configured to discharge a mixed liquid of the water repellent-containing liquid and the decomposition solution to an outside of the substrate treating apparatus, wherein
• the substrate treating unit includes:
• a chamber configured to accommodate the substrate;
• and
• a water repellent nozzle configured to supply the water repellent to the substrate accommodated in the chamber,
• the decomposition solution mixing mechanism includes a first decomposition solution mixing unit,
• the discharging unit includes:
• a water-sealing vacuum pump configured to exhaust gas within the chamber;
• a seal water tank configured to store seal water;
• a pump exhaust pipe configured to connect the water-sealing vacuum pump and the seal water tank for feeding gas in the chamber and the seal water from the water-sealing vacuum pump to the seal water tank;
• a circulating pipe configured to connect the seal water tank and the water-sealing vacuum pump for returning the seal water from the seal water tank to the water-sealing vacuum pump;
• a seal water tank exhaust pipe whose first end is connected to the seal water tank;
• a seal water tank drain pipe whose first end is connected to the seal water tank;
• a second mixing unit connected to a second end of the seal water tank drain pipe;
• and
• a second mixing unit drain pipe whose first end is connected to the second mixing unit,
• the first decomposition solution mixing unit mixes the decomposition solution to the seal water, passing through the second mixing unit, via the second mixing unit when the discharging unit discharges the seal water as the water repellent-containing liquid from the seal water tank, and
• the discharging unit discharges the mixed liquid through the second mixing unit drain pipe to the outside of the substrate treating apparatus.