Method for regulating pressure of dresser in chemical mechanical polishing

Abstract

The invention discloses a method for regulating pressure of a dresser in chemical mechanical polishing, and belongs to the field of semiconductor chip processing and manufacturing. The method comprises the following steps of, in the whole motion path of the dresser, dividing pressure control into two parts, and distinguishing according to the contact area of the dresser and a polishing pad: (1) when the dresser is in complete contact with the polishing pad, the pressure applied to the polishing pad by the dresser is F1, wherein F1 is preset constant pressure; and (2) during incomplete contact,the pressure applied to the polishing pad by the dresser is F2, and F2 changes along with the change of the contact area between the dresser and the polishing pad, so that all regions of the polishing pad are subjected to the same dressing pressure intensity. By means of the method for regulating the pressure of the dresser in chemical mechanical polishing, the edge effect phenomenon that the edge of the polishing pad is consumed too fast can be eliminated, the thickness difference between the middle part and the edge part of the polishing pad is improved, and the service life of the polishing pad is prolonged.

Description

technical field [0001] The invention relates to a method for adjusting the pressure of a dresser in chemical mechanical grinding, and belongs to the field of semiconductor chip processing and manufacturing. Background technique [0002] In the field of semiconductor chip processing and manufacturing, with the upgrading of process technology, photolithography technology has higher and higher requirements for the flatness of the wafer surface. The combination of chemical etching and mechanical grinding is currently the only technology that can achieve global planarization of the surface. In the process of chemical mechanical polishing, the wafer is in close contact with the polishing pad and a certain pressure is applied for relative movement. During this process, the roughness of the polishing pad and the overall shape change have a great impact on the polishing rate and flatness. In order to ensure that the mechanical removal rate of the wafer is stable and constant, it is ...

AI Technical Summary

Problems solved by technology

The reason is that when the dresser moves to the edge of the polishing pad, the pressure exerted by the dresser remains unchanged, but the force-bearing area between the polishing pad and the dresser decreases, resulting in an increase in the pressure on the polishing pad and a decrease in the consumption of the polishing pad. Large, after a long time, there is a difference in the thickness of the middle part and the edge part of the polishing pad

Since the polishing pad as a consumable affects the cost of manufacturing and processing, it also affects the mechanical grinding and manufacturing of silicon wafers, which affects the effect of achieving global planarization of the wafer.

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