Immersion liquid supply system and immersion flow field initial establishment method

Abstract

The invention relates to an immersion liquid supply system and an immersion flow field initial establishment method. The immersion liquid supply system is characterized in that a first flow path comprises an immersion liquid purification assembly, the immersion liquid purification assembly can improve the purity of an immersion liquid, a second flow path comprises a liquid supply valve, the liquid supply valve controls whether to supply the immersion liquid to an immersion liquid supply and recovery device, a third flow path comprises a bypass valve, the bypass valve controls on-off of the third flow path, and the immersion liquid supply system further comprises an immersion liquid flow adjusting assembly which can enable flow parameters of immersion liquid to tend to be within the range required by exposure. According to the invention, the purity and flow parameters of the immersion liquid can be close to the exposure requirement range of a photoetching machine; pollution of pollutants in the immersion liquid to components in the immersion liquid supply system is reduced; and pollutants are prevented from entering an immersion flow field and even being attached to the wall surface of the immersion flow field, the initial establishment process of the immersion flow field is accelerated, the reliability of pollutant elimination in the initial establishment process of the immersion flow field is improved, and the efficiency of the photoetching machine is improved and the exposure quality is ensured.

Description

technical field [0001] The invention belongs to the technical field of immersion photolithography machines, and relates to an immersion liquid supply system and an initial establishment method of an immersion flow field. Background technique [0002] The lithography machine is one of the core equipment for manufacturing VLSI. It uses the optical system to accurately project the circuit pattern on the mask onto the photoresist-coated substrate and modify the photoresist exposure to modify the photoresist. Circuit pattern information is left on the substrate. It includes a laser light source, a projection objective lens system, a projection mask containing circuit patterns and a substrate coated with photosensitive photoresist. [0003] Compared with the dry lithography machine in which the intermediate medium is gas, the immersion lithography (Immersion Lithography) equipment fills a liquid with a high refractive index (called immersion liquid or immersion liquid) between th...

AI Technical Summary

Problems solved by technology

Before the immersion liquid flows into the flow path of the immersion liquid supply system, there may be pollutants such as particles, and the flow of the immersion liquid in the flow path may generate air bubbles and pollutants due to structural gaps and corners. The pollutants flow into the immersion flow with the immersion liquid. After the field, it may be attached to the surface of the projection objective lens and the substrate, causing pollution to the surface of the projection objective lens and the substrate

Eliminating pollutants attached to the surface of the projection objective lens and the substrate prolongs the time consumed for the initial establishment of the immersion flow field and reduces the working efficiency of the lithography machine; and these pollutants may have a strong ability to attach to the solid surface, and may Difficult to remove, degrades exposure quality during exposure

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