초록 ▼

A system for eliminating air from liquid-carrying conduits, in particular in a photoresist dispensing system, with features for reducing the possibility of contamination by residual resist in the conduits after the air elimination process has been carried out. Double or multiple tubing, with one or

A system for eliminating air from liquid-carrying conduits, in particular in a photoresist dispensing system, with features for reducing the possibility of contamination by residual resist in the conduits after the air elimination process has been carried out. Double or multiple tubing, with one or more secondary tubes contained within an outer tube, is used to interconnect the trap tank, the drain and the vacuum chamber. Resist is directed through the double or multiple tubing such that resist is completely evacuated from the vacuum chamber, and from the trap tank, to the drain valve. Further, an arrangement for avoiding the consequences of contamination of the air exhaust valve in the system, if a mist of residual resist has not been removed by the air elimination process, includes a vacuum generator downstream from the air exhaust valve. The vacuum from the vacuum generator is applied as a negative pressure downstream from the valve rather than a positive pressure upstream from the valve, thus reducing the possibility of air or contamination being forced backwards through the system by a blockage of the air exhaust valve.

대표청구항 ▼

A photoresist dispensing system comprising: a trap tank for receiving resist from a resist supply, and for dispensing said resist; a sensor associated with said trap tank which is operative to detect an excess of gas in said trap tank and to issue a sensor signal in response thereto; a vacuum genera

A photoresist dispensing system comprising: a trap tank for receiving resist from a resist supply, and for dispensing said resist; a sensor associated with said trap tank which is operative to detect an excess of gas in said trap tank and to issue a sensor signal in response thereto; a vacuum generator connected to said trap tank by a vacuum line, said vacuum generator being responsive to said sensor signal; and in response thereto, generating a vacuum on said vacuum line to draw resist from said resist supply so as to fill said trap tank and said vacuum line and thereby eliminate said excess gas from said trap tank; said vacuum generator comprising: a Venturi arranged for generating a vacuum on said vacuum line in response to an air flow through said Venturi; an exhaust valve connected to an outlet on a downstream side of said Venturi for controlling said air flow; and a second vacuum generator downstream from said exhaust valve for drawing air through said exhaust valve and thereby creating said air flow through said Venturi to generate said vacuum on said vacuum line.