System and method for carrying out in-situ detection on odd aberration of projection objective for photoetching machines

Abstract

The invention discloses a system and method for carrying out in-situ detection on the odd aberration of a projection objective for photoetching machines. The system comprises a light source, a lighting system, a masking platform, a mask, a projection objective, an operating platform, an image sensing device, an interferometer and a data processing device, wherein the mask contains a detection mark, and the interferometer is used for position control. The method comprises the following steps: calibrating corresponding odd-aberration sensitivity coefficients of the projection objective through setting different partial coherence factors and numerical apertures; then, measuring the value of difference between the peak value and light intensity of a space image of the detection mark by using the image sensing device; and finally calculating the odd aberration of the projection objective by using the calibrated odd-aberration sensitivity coefficients. The system and method disclosed by theinvention have the advantage of improving the accuracy of detection on the odd aberration of the projection objective for photoetching machines.

Description

technical field [0001] The invention relates to a lithography machine, in particular to an in-situ detection system and detection method for odd aberrations of a projection objective lens of a lithography machine. Background technique [0002] Photolithography technology is the core technology in the VLSI manufacturing process, and it affects the technology nodes that can be realized in the VLSI manufacturing process. The step-and-scan projection lithography machine is an important equipment used in the lithography process, and the projection objective lens system is one of the important subsystems of the lithography machine. The wave aberration of projection objective lens has an important influence on the photolithography process. According to the distribution characteristics of wave aberration, wave aberration can be divided into odd aberration and idol aberration. For example, coma and triple wave aberration are odd aberrations, and spherical aberration and astigmatism ...

AI Technical Summary

Problems solved by technology

[0006] Prior Art 1, Prior Art 2, and Prior Art 3 all use the imaging position offset as the measurement object when detecting the odd aberration of the projection objective lens, and the measurement accuracy of the aberration is limited by the accuracy of the displacement measurement tool and the positioning device. influence, which limits the further improvement of wave aberration detection accuracy using this technology

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