A method and system for searching alignment marks by lithography machine

Abstract

The invention discloses a method and a system for a lithography machine to search for an alignment MARK, comprising the following steps: S1: Put a substrate with a MARK mark point on a positioning platform, and move the positioning platform so that the MARK mark point is on the lithography machine The theoretical coordinate position in , S2: within the set search range, calculate the search path of the positioning platform by the spiral path method, S3: fix the CCD camera to keep still, drive the positioning platform to move according to the search path to drive the substrate to move synchronously, S4 : During the moving process of the positioning platform with the substrate, the CCD camera collects the image of the substrate graphics in real time, and aligns the MARK mark points; the platform with the substrate moves through the search path, and the CCD camera collects the substrate graphics during the movement of the positioning platform and performs corresponding Image splicing processing, through image processing algorithm to accurately align MARK mark points, solves the problems of poor exposure quality and production capacity caused by inaccurate alignment of MARK mark points during exposure of traditional lithography machines.

Description

technical field [0001] The present invention relates to the technical field of exposure alignment of lithography machines, in particular to a method and system for searching alignment MARKs of lithography machines. Background technique [0002] Photolithography is used to print a pattern of features on the surface of a substrate. Such substrates may include chips used in the manufacture of semiconductor devices, various integrated circuits, flat panel displays, circuit boards, biochips, micromechanical electronic chips, optoelectronic circuit chips, and the like. [0003] In modern microelectronics, the manufacture of integrated circuits is a precision microfabrication technology, including a series of processes such as photolithography, ion implantation, etching, epitaxial growth, and oxidation. The photolithography process refers to the process of transferring the pattern to the photoresist on the surface of the silicon wafer through exposure and development processes, so...

AI Technical Summary

Problems solved by technology

Due to the precision requirements of exposure products, it is usually processed with a lens of 10X and above. When aligning, the traditional spiral search method is used to find the MARK mark point. The range of a single MARK may occupy half the size of the field of view, and there may be only part of the MARK. The graphics are in the field of view, which brings many problems to the detection, and finally leads to poor exposure quality; it may also occur that the position of the film is more than a certain distance from the theoretical position, the search time is too long, and the production capacity cannot be increased; and the above exposure quality is poor. The problem of not being able to increase the production capacity is due to the inaccuracy of finding and aligning the MARK mark points

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