Mask set and method for detecting alignment precision by utilizing mask set

Abstract

The invention discloses a mask set and a method for detecting the alignment precision by utilizing the mask set, and provides a novel mask set and a method for detecting the alignment precision by utilizing the mask set. The mask set comprises a first mask and at least one second mask; each second mask comprises one or more point positions for detecting the alignment precision; the area, corresponding to the point position, of the first mask is provided with at least one first alignment mark, and the first alignment mark is a line segment with a set length; the area, corresponding to the point positions, of the second mask is provided with second alignment marks corresponding to the first alignment marks one by one, and each second alignment mark is a line segment with a set length; the projection of the first alignment marks on the first mask is intersected with that of the second alignment marks on the first mask, and the projection of the first alignment mark and the projection of the second alignment mark form a set angle.

Description

technical field [0001] The invention relates to the technical field of photolithography technology, in particular to a mask plate set and a method for detecting overlay accuracy by using the mask plate set. Background technique [0002] Photolithography is an important step in the manufacturing process in the semiconductor field. Photolithography is the process of transferring the pattern on the mask (Mask) to the target substrate through the steps of alignment, exposure and development. A product generally includes multi-layer functional film layers, and a multi-layer photolithography process is required to complete the entire product manufacturing process. It is particularly important to align the photolithographic pattern of the current functional film layer with the photolithographic pattern of the previous functional film layer. Overlay Accuracy refers to the positional alignment deviation of lithographic patterns between different functional film layers, and the size...

AI Technical Summary

Problems solved by technology

[0005] (1) When the measurement coordinate system cannot be established on the test equipment, the overlay accuracy cannot be detected

[0006] (2) When the Overlay Mark part is missing, the overlay accuracy cannot be accurately detected

[0007] (3) When the subsequent mask plate is rotated relative to the previous mask plate, the rotation of the mask plate cannot be detected, and accordingly the offset of the mask plate cannot be detected

[0008] (4) Determine the alignment deviation between the overlay marks of each test point through the test program (also called the test recipe). When the test equipment and the test point are determined, the test recipe is also determined. If you want to test more When pointing, it is necessary to rewrite the test program, and the work efficiency is low

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