Method for prolonging service-life of grinding pad in chemical-mechanical polishing

Abstract

The present invention discloses a method for prolonging grinding pad life in chemical and mechanical polishing process. Said method includes the following steps: first step, measuring grinding pad groove depth and grinding pad thickness of grinding pad in different use stages so as to define cutting speed of grinding pad in different zones; second step, setting residence time of correction disk in different zones of grinding pad; third step, detecting the grinding grain of different zones of grinding pad and grinding rate for chemical and mechanical polishing; fourth step, measuring the grinding pad groove depth and grinding pad thickness of grinding pad which is used to its life; fifth step, according to the detection results obtained by above-mentioned several steps setting pressure of correction disk in the different zones of grinding pad; and sixth step, repeating third step to fifth step until the proper pressure parameter is found, making surface loss of every zone of grinding pad and groove depth be identical.

Description

technical field [0001] The invention relates to a chemical mechanical polishing process in the field of semiconductor integrated circuit manufacturing, in particular to a method for prolonging the service life of a grinding pad in chemical mechanical polishing. Background technique [0002] The chemical mechanical polishing pads currently used in the field of integrated circuit manufacturing have a single groove width and depth across the entire surface of the polishing pad. However, due to the process application, the time that the silicon wafer acts on different areas of the polishing pad is different, including the time that the correction disc acts on different areas on the polishing pad. These two factors cause the consumption of the polishing pad to be in-plane. Inhomogeneity, resulting in poor process uniformity. Fig. 1 is a comparison diagram of the thickness of the polishing pad before and after use in the prior art, and Fig. 2 is a comparison diagram of the depth ...

AI Technical Summary

Problems solved by technology

) Due to the excessive local loss of the polishing pad, the uniformity of chemical mechanical polishing or the grinding rate exceeds the specification, and finally the polishing pad can only be replaced

This is a waste in the chemical mechanical polishing process

There are many consumables used in chemical mechanical polishing. In the chemical mechanical polishing process of the prior art, in the parameter setting of the correction disc, only the residence time in each area of ​​the polishing pad is set differently, which affects the life of the polishing pad. , resulting in waste, but also reduces the uniformity of the chemical mechanical polishing process in the silicon wafer

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