Gas-seal and gas-liquid vibration damping recovery device used in immersion lithographic machine

Abstract

The invention discloses a gas-seal and gas-liquid vibration damping recovery device used in an immersion lithographic machine. The gas-seal and gas-liquid vibration damping recovery device is arranged between a projection lens group of the immersion lithographic machine and a silicon wafer; the gas-seal and gas-liquid vibration damping recovery device comprises a sealing and injected liquid recovery device, and a porous medium. The sealing and injected liquid recovery device is composed of an immersion unit upper end cap, an immersion unit middle body, an immersion unit lower end cap, and immersion unit lower end cap parts. The device provided by the invention is used for accomplishing functions of sealing and injected liquid recovery of a gap flow field of an immersion lithographic system, such that gap flow field continuous and stable renewing can be realized. The gas seal structure is adopted in the edge of the gap flow field, such that liquid leakage is prevented; with the gas-liquid vibration damping recovery structure, gas and liquid recovery are realized; under a condition of low speed, the appearance of a gas-liquid two-phase flow is avoided; under a condition of high speed, vibration caused by gas-liquid two-phase flow is reduced; no matter what direction the silicon moves in, with a buffering cavity structure, the gap flow field has a self-adaptive adjusting function.

Description

technical field [0001] The invention relates to a flow field sealing and recovery device, in particular to an air sealing and gas-liquid vibration damping recovery device for an immersion photolithography machine. Background technique [0002] The lithography machine is one of the core equipment for manufacturing VLSI. The modern lithography machine is mainly optical lithography. It uses the optical system to accurately project and expose the pattern on the mask to the photoresist-coated surface. on a silicon wafer. It includes a laser light source, an optical system, a projection mask composed of chip patterns, an alignment system and a silicon wafer coated with photosensitive photoresist. [0003] Immersion lithography (Immersion Lithography) equipment fills a liquid with a high refractive index between the last projection objective lens and the silicon wafer, which improves the numerical aperture of the projection objective lens ( NA), thereby improving the resolution a...

AI Technical Summary

Problems solved by technology

During the high-speed movement of the substrate, once the external air or sealing liquid is involved or dissolved or diffused into the filling liquid, it will have a negative impact on the exposure quality

[0005] (2) The existing air sealing method uses an air curtain to apply around the filling fluid, causing instability at the edge of the flow field. During the high-speed stepping and scanning process of the substrate, it may cause liquid leakage and entrainment of sealing gas to the flow field At the same time, when the filling liquid and the sealing gas are recovered together, a gas-liquid two-phase flow will be formed, which will cause vibration and affect the stable operation of the exposure system

[0006] In the existing solution, the air seal is better, but the existing air seal device has the problem of gas-liquid two-phase flow in the recovery process, and the recovery of the two together will cause the vibration of the pipeline. thus seriously affecting the exposure quality

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