Patent ID: 7014715
Filing Date: 2006-03-21
Classification: G03F,H01L

Abstract:
1. A photoresist supply apparatus for use in coating equipment, comprising: first and second bottles for use in storing solutions of photoresist; a source of N first and second gas supply pipes each connecting a respective one of the first and second bottles to said source of N first and second solenoid valves disposed along the first and second gas supply pipes, respectively, said first and second solenoid valves each being switchable between respective positions at which the N first and second photoresist supply pipes connected to upper parts of the first and second bottles, respectively, to supply photoresist solution from the bottles; first and second trap tanks connected to the first and second photoresist supply pipes, respectively, to receive photoresist supplied from the first and second bottles; a third photoresist supply pipe connected to the first and second trap tanks; a nozzle connected to the third photoresist supply pipe so as to spray the photoresist solution supplied through the third photoresist supply pipe; first and second level sensors each operatively associated with an upper part of a respective one of the first and second trap tanks so as to sense when the photoresist solution in the tank falls below a first level; third and fourth level sensors each operatively associated with a lower part of a respective one of the first and second trap tanks so as to sense when the photoresist solution in the tank falls below a second level lower than said first level; first and second discharge pipes each connected to an upper part of a respective one of the first and second trap tanks so as to allow photoresist solution in the trap tanks to be discharged; third and fourth solenoid valves disposed along the first and second discharge pipes, each of said third and fourth solenoid valves being switchable between respective positions at which the photoresist solution is discharged from a said trap tank through a said discharge pipe and the discharging thereof is cut off; first and second drain sensors operatively associated with said discharge pipes, respectively, so as to sense whether photoresist solution is being discharged through the discharge pipes; first and second purge start buttons operative to generate a purge start key signal when manipulated; and a controller operatively connected to said first and second purge start buttons so as to receive the purge start key signals therefrom, operatively connected to said level sensors so as to receive signals therefrom indicative of the level of photoresist solution in said trap tanks, operatively connected to said drain sensors so as to receive signals therefrom indicative of whether photoresist solution is being discharged through the discharge pipes, and operatively connected to said solenoid valves so as to switch said valves between respective positions thereof based on said purge start key signals and the signals from said drain sensors.