Position information measuring method and device, and exposure method and system

Abstract

A position information measurement method that can simply obtain the relative position deviation information of two markers by means of scattering measurement or reflection measurement. Marks (25A) are previously formed on the wafer (W) at intervals P1, and marks (28A) are formed on the intermediate layer (27) thereon at a pitch P2 different from the pitch P1. The detection light (DL) is perpendicularly incident on the wafer (W), and only the regular reflection light (22) from the two marks (25A, 28A) is split according to the wavelength, and photoelectric conversion is performed. The reflectance at each wavelength is obtained from the obtained detection signal, the reflectance at a predetermined wavelength is obtained for each position of the marks (25A, 28A) in the measurement direction (X direction), and the obtained reflectance distribution is obtained. From the shape of the wave pattern formed by the overlapping of the two marks (25A, 28A), the positional deviation amount of the mark (28A) is obtained from the shape.

Description

technical field [0001] The present invention relates to a method and device for measuring position information using so-called scatterometry (Scatterometry) or reflectometry (Reflectometry) to obtain information related to the relative positional deviation of two marks, and is applicable to aligning a mask and a substrate in an exposure step , and the evaluation of the overlay error after exposure, etc., the exposure step is to transfer mask patterns of various devices such as semiconductor elements, imaging elements (CCD, etc.) or display elements (liquid crystal display elements, etc.) to on the substrate. Background technique [0002] In the exposure step in the photolithography process used to manufacture semiconductor elements and liquid crystal display elements, using an exposure device such as a stepper, the reticle formed on a reticle (reticle, or photomask, etc.) The image of the fine pattern is projected and exposed onto a semiconductor wafer (or glass plate, etc....

AI Technical Summary

Problems solved by technology

However, in the method of imaging the image of the mark with such a large numerical aperture optical system, measurement errors are likely to occur due to the influence of the aberration of the optical system and the skew of the mark.

In addition, there is a possibility that the reproducibility of measurement results may be reduced due to the influence of the vibration of the test object on which the mark is formed.

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