Chemical mechanical grinding equipment and method

Abstract

Disclosed is chemical mechanical grinding equipment and method. The chemical mechanical grinding equipment comprises a piece carrying platform, a grinding mechanism, a grinding liquid injecting mechanism, a grinding cleaning mechanism and a film thickness measuring mechanism, the grinding mechanism comprises a grinding member capable of repeatedly moving along a second linear direction which is perpendicular to a first linear direction, the grinding liquid injecting mechanism is used for injecting grinding liquid into the grinding member, the grinding cleaning mechanism is arranged opposite to the grinding mechanism along the first linear direction, and the film thickness measuring mechanism is used for measuring thickness a to-be-ground piece after being cleaned. In the process of chemical mechanical grinding, the to-be-ground piece during moving is ground, cleaned and measured at the same time. By using the chemical mechanical grinding equipment, the thickness of the to-be-ground piece after being ground can be measured in real time, grinding quantity of the to-be-ground piece in the process of grinding is controlled, the thickness of the to-be-ground piece after being ground is ensured to be target thickness, product qualification rate is increased, waste piece number is reduced, and production cost is lowered.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a chemical mechanical polishing device and method. Background technique [0002] refer to figure 1 , figure 1 It is a schematic diagram of an existing chemical mechanical polishing equipment, which includes: a rotatable platform 1 ; a polishing pad 2 covering the platform 1 ; a rotatable polishing head 3 and a polishing liquid nozzle 4 . [0003] Taking a silicon wafer as an example, the method of chemical mechanical polishing is as follows: the silicon wafer 5 is turned upside down so that the surface to be polished contacts the grinding pad 2; then the grinding head 3 is pressed on the silicon wafer 5; then, the control platform 1 rotates and the rotation of the grinding head 3, while controlling the grinding fluid nozzle 4 to spray the grinding fluid 40 on the grinding pad 2, and applying downward pressure towards the silicon wafer 5 to the grinding head ...

AI Technical Summary

Problems solved by technology

[0004] Along with the grinding process, the surface of the grinding pad is also gradually worn and uneven during the grinding process. In this way, during the grinding process, for silicon wafers ground under the same pressure and rotation speed, the grinding rate will increase over time. changes, resulting in a decrease in the thickness uniformity of the polished silicon wafer

Since the existing chemical mechanical polishing process lacks an effective method for real-time monitoring of the thickness of the polished silicon wafer, the thickness of the silicon wafer and its changes during the grinding process cannot be obtained in real time, and it cannot be found in time: due to the wear and tear of the grinding pad The thickness uniformity of the polished silicon wafer is significantly reduced. If you continue to use the polishing pad for grinding, a large number of polished silicon wafers will be scrapped and the production output will be reduced.

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