Liquid delivering and airtight device in submersible photoetching system

Abstract

The invention discloses a liquid transmission and air sealing device in an immersion photolithography system. A liquid transmission and air sealing device is installed between the projection lens in the immersion lithography system and the silicon wafer to be exposed. The liquid transmission and air sealing device is coaxial from bottom to top in sequence with air pressure equalization Inlet parts with air pressure equalization structure, exhaust parts with air pressure equalization structure, liquid injection and recovery parts and end cover assembly; air intake parts with air pressure equalization structure and exhaust parts with air pressure equalization structure Both adopt a labyrinthine three-layer annular airway structure. There are two, four and eight annular short grooves between the air passages respectively. The multi-layer air passages and the grooves between the air passages are used to obtain stable flow and uniform pressure difference at the gas sealing boundary. On the one hand, it prevents Liquid leakage is prevented, and air bubbles are also prevented on the other hand.

Description

technical field [0001] The invention relates to a liquid conveying and air-sealing device in an immersion lithography system, in particular to a liquid conveying and air-sealing device that transmits liquid in a gap between a projection lens end element and a silicon wafer and ensures no leakage of the liquid . Background technique [0002] Modern lithography equipment is based on optical lithography, which uses an optical system to accurately project and expose patterns on a mask onto a photoresist-coated silicon wafer. It consists of a UV light source, an optical system, a projection reticle consisting of chip patterns, an alignment system and a silicon wafer covered with photosensitive photoresist. [0003] The immersion lithography system fills the gap between the projection lens and the silicon wafer with a certain liquid. By increasing the refractive index of the medium in the gap, the numerical aperture of the projection lens is increased, thereby improving the resol...

AI Technical Summary

Problems solved by technology

However, in the various hermetic structures proposed by it, there are problems such as uneven flow and pressure concentration at the gas-sealed boundary, and the uneven air flow is not conducive to liquid sealing on the one hand, and causes leakage during the scanning lithography process. Bubbles may be generated on the one hand, and the bubbles enter the exposure field between the projection lens and the silicon wafer, which will affect the image quality

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