Levelling device and levelling method for polishing head

Abstract

The invention discloses a levelling device and a levelling method for a polishing head. The levelling device comprises a spline shaft, a spline hub, a bearing sleeve, a bearing end cap, a bearing pre-tightening ring, a bearing, an adjusting panel, a base plate and at least three levelling screw sets; the adjusting panel is arranged on the upper surface of the base plate; the bearing end cap is matched with the bearing pre-tightening ring for pre-tightening the outer ring of the bearing; the bearing is arranged between the spline hub and the bearing sleeve; the spline shaft is accommodated in the spline hub; and each levelling screw set is connected onto the adjusting panel. According to the levelling device, levelling operation is transferred to the polishing head through the spline shaft, and the area of the polishing head is large, so that the polishing head is applicable to polishing of wafers with large sizes. Loosening-proof flanges are used for eliminating threaded clearances between levelling nuts and the adjusting panel; the levelling precision is improved; and the phenomenon that a pre-levelled position is changed by friction force during a process of rotating fastening bolts is prevented.

Description

technical field [0001] The invention relates to the field of chemical mechanical polishing in semiconductor manufacturing, in particular to a polishing head leveling device and method. Background technique [0002] In the field of IC (integrated circuit) manufacturing, thinning is the first process in the processing of finished wafers. The initial thickness of the wafer is generally 675um-775um, and eventually it will be thinned to 100um-200um, and in some specific industries, it will even be thinned to 20um. In the wafer thinning process, due to the existence of the mechanical damage layer, the fragmentation rate is very high during transportation and subsequent processes, and generally the wafer cannot be directly ground to the thickness required for chip packaging. In practical applications, firstly, the wafer is ground to a thickness close to the target thickness by backside thinning, most of the margin is removed by grinding, and then the damage layer and residual stre...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to solve the technical problems of large volume, high cost and small size of wafers that can be polished in the leveling device of the current wafer polishing equipment

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