Precision Pump With Multiple Heads

Abstract

A high purity, high precision pump capable of pumping more than one type of chemistry or process fluid without requiring cleaning or changing of surfaces contacting the processing fluid. The pump employs a single drive mechanism coupled in parallel with multiple pumping chambers, each capable of handling a different type of manufacturing fluid. The pump can be utilized as part of a single stage or multi-stage pump system.

Description

TECHNICAL FIELD OF THE INVENTION[0001]The present invention relates generally to apparatus used in metering fluids with high precision, particularly in fields such as semiconductor manufacturing.BACKGROUND OF THE INVENTION[0002]Many of the chemicals used in manufacturing integrated circuits, photomasks, and other devices with very small structures are corrosive, toxic and expensive. One example is photoresist, which is used in photolithographic processes. In such applications, both the rate and amount of a chemical in liquid phase—also referred to as process fluid or “chemistry”—that is dispensed onto a substrate must be very accurately controlled to ensure uniform application of the chemical and to avoid waste and unnecessary consumption. Furthermore, purity of the process fluid is often critical. The smallest of foreign particles contaminating a process fluid causes defects in the very small structures formed during such processes. The process fluid must therefore be handled by a ...

AI Technical Summary

Benefits of technology

[0007]In contradistinction to typical deployments of pumps in such applications, particularly those used for high-precision metering, an exemplary pump employing teachings of a preferred embodiment of the invention is capable of pumping more than one type of chemistry or process fluid without requiring cleaning or changing of surfaces contacting the processing fluid. The pump employs multiple pumping heads, each capable of handling a different type of manufacturing fluid. At least two of the pumping heads share a common actuating mechanism. Although a multi-headed pump might be larger when compared to a pump with a single head, utilizing fewer actuating mechanisms than pumping heads saves valuable space in crowded processing facilities, such as those used for fabricating semiconductor components, which use a large number of pumps. Since actuation mechanisms are sometimes the most complex part of a pump, fewer actuating mechanisms in a factory saves money and maintenance time.

[0008]Sharing a single actuating mechanism among multiple heads may seem undesirable, particularly for fluid metering applications. Having a shared actuation mechanism typically means that only one pumping head may be actuated at a time. However, in one exemplary embodiment, the multi-headed pump is capable of fast and frequent switching between pump heads. With actuation between pump heads capable of being switched quickly, there is little delay between demand for dispense and dispense in applications having very short dispense cycles due to relatively small amounts of fluid that are being dispensed.

Problems solved by technology

Although a multi-headed pump might be larger when compared to a pump with a single head, utilizing fewer actuating mechanisms than pumping heads saves valuable space in crowded processing facilities, such as those used for fabricating semiconductor components, which use a large number of pumps.

Since actuation mechanisms are sometimes the most complex part of a pump, fewer actuating mechanisms in a factory saves money and maintenance time.

Sharing a single actuating mechanism among multiple heads may seem undesirable, particularly for fluid metering applications.

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