Etching method and system

Abstract

The invention discloses an etching method and an etching system, wherein the method comprises the following steps of: after main etching is stopped, judging whether etching stopping points are caught when the main etching is stopped, and if not, entering an over-etching step for continuously catching the etching stopping points; when the over-etching step reaches the preset maximum over-etching time, after the etching stopping points are caught and normal over-etching time is passed, automatically stopping; after the over etching is stopped, judging whether etching stopping points are caught or not before the over etching is stopped, and if so, obtaining a correction value of the maximum main etching time according to the etching thickness and the maximum main etching time; and adopting the correction value of the maximum main etching time to carry out next-time etching process. According to the embodiment of the invention, by the introduction of a judgment mechanism and a time feedback mechanism and control for the etching mode of etching equipment, the problems of the etching residual and slightly-large device CDs (Compact Discs) and the like after over-etching due to over-early stopping of the main etching in the prior art are solved.

Description

Technical field [0001] The present invention relates to the technical field of semiconductor manufacturing, and more specifically, to an etching method and system. Background technique [0002] With the rapid development of Ultra Large Scale Integration (ULSI), integrated circuit manufacturing processes have become more and more complex and sophisticated, and the requirements for etching effects have become more and more stringent. At present, the etching steps in the production process of semiconductor devices are generally divided into two steps: main etching and over-etching. The main etching adopts the method of capturing the etching stop point to stop the main etching in a timely manner, but if it reaches the preset maximum The main etching time still does not find the etching stop point, and the main etching will also be stopped, and then the over-etching is performed with a fixed etching time to avoid etching residue. [0003] However, the above-mentioned etching methods in...

AI Technical Summary

Problems solved by technology

In this way, after the etching stop point, the actual overetching time is less than the normal overetching time, that is, the thickness of the metal layer etched during the entire etching process is actually less than the normal etching thickness. In this case, It is often easy to cause etching residues on the metal layer, or the CD (critical dimension) of the device is too large and other adverse consequences

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