System error self-corrected online detecting device of projection objective lens wave aberration of photo-etching machine

Abstract

The invention provides a system error self-corrected online detecting device of projection objective lens wave aberration of a photo-etching machine, which can detect the projection objective lens wave aberration of the photo-etching machine at high precision. By using an object mask plate provided with a square pinhole array, an ideal spherical wave is generated by using the square pinhole arrayto eliminate the influences of an illuminating system on the detection of the projection objective lens wave aberration of the photo-etching machine so as to improve the detecting precision. By usingsystem error self-correction of the pinhole array filtering, a square hole mask plate and a pinhole array mask plate are respectively placed at an object face and an image face of the projection objective lens of the photo-etching machine so as to realize spatial filtering of residual aberration of the illuminating system to be detected and the projection objective lens wave aberration while the utilization rate of an exposure light source is assured, thus the projection objective lens wave aberration can be fast obtained with high precision.

Description

technical field [0001] The invention belongs to the field of optical detection, and in particular relates to an on-line detection device for wave aberration of a projection object lens of a photolithography machine with self-calibration of system errors. Background technique [0002] With the improvement of lithography resolution, the residual wave aberration of the projection objective lens of lithography machine is required to be smaller and smaller. The three major companies ASML, Canon and Nikon directly use high-precision phase measurement interferometers (PMI for short) when processing and integrating projection objective lenses for lithography machines, such as Tieman-Green interferometers and Fizeau interferometers. The residual wave aberration of the engraving machine projection objective lens is detected. However, in practice, due to factors such as transportation and assembly, the wave aberration of the objective lens projected by the lithography machine will cha...

AI Technical Summary

Problems solved by technology

However, since the detection device uses a square hole to expand the light source, the residual aberration of the illumination system cannot be eliminated, and the device calibrates the system error by axially moving the image square square hole mask, because the working distance of the collimating objective lens is limited The axial movement range of the square hole mask plate limits the spatial filtering effect of the square hole mask plate on the wave aberration of the lithography projection objective lens and the residual aberration of the illumination system

Due to the above two shortcomings, to a certain extent, the further improvement of the detection accuracy of the orthogonal phase grating transverse shear interferometer device is limited.

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