Chemical mechanical polishing apparatus and method thereof

Abstract

The invention relates to a chemical mechanical polishing apparatus and a method thereof. The apparatus comprises a polishing head for pressing and rotating a wafer in a state where the wafer is on a lower side; a height measuring portion for obtaining a height deviation in the radial direction of a polishing pad during the chemical mechanical polishing; a regulating device having an arm portion and an adjusting disc, the arm being rotated about a hinge axis to rotate at a predetermined angle, and the adjusting disc pressing the polishing pad against the lower side of the arm portion and rotating; and a control portion for adjusting the rotational speed of the arm portion with a second rotation speed at a second position, the height of the polishing pad at the second position being higher than the height at the first position, and the second rotational speed being smaller than the first rotational speed, such that, by adjusting the rotational speed of the adjusting disc, it is possible to alleviate the height deviation of the polishing pad at different positions. Therefore, even if the same pressure is applied to the wafer, the friction amount is different depending on the height deviation of the polishing pad, so that the polishing amount per hour of the wafer can be adjusted in each region.

Description

technical field [0001] The present invention relates to a chemical mechanical polishing device and a method thereof, more particularly to a chemical mechanical polishing device and a method thereof capable of accurately controlling the thickness of a polishing layer of a wafer by correcting the height deviation of the polishing pad in real time during the chemical mechanical polishing process. Background technique [0002] In general, the chemical mechanical polishing (CMP) process refers to a standard process for polishing the surface of the wafer by relatively rotating the wafer, such as a semiconductor manufacturing wafer provided with a polishing layer, and a polishing plate. [0003] figure 1 It is a diagram schematically showing a conventional chemical mechanical polishing apparatus 9 . Such as figure 1 As shown, above-mentioned chemical mechanical polishing device 9 comprises: polishing plate 10, is attached with polishing pad 11 on the upper surface; and rotate; t...

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Problems solved by technology

[0009] But, the slurry 40a supplied to the polishing pad 11 from the slurry supply part 40 cannot be smoothly spread on the surface of the polishing pad 11 due to the height deviation 79 of the polishing pad 11, and the chemical polishing process by means of the slurry cannot be performed as expected. implementation, and as compared with the wafer polishing layer region in contact with the relatively lower surface height region E2 of the polishing pad 11, since each of the wafer polishing layer regions in contact with the relatively higher surface height region E1 of the polishing pad The hour polishing layer removal rate (removalrate) is higher, therefore, there is limitation in adjusting the polishing layer thickness of wafer in the mode that changes the applied pressure of each area of ​​wafer by polishing head 20

[0010] That is, according to the prior art, it has also been attempted to adjust the height deviation 79 of the polishing pad during the chemical mechanical polishing process, but since the height deviation of the polishing pad cannot be adjusted in a short time, even if the pressure applied to the wafer by the polishing head is uniform , the polishing layer thickness distribution of the wafer will also occur due to the pressure deviation caused by the height deviation of the polishing pad, which cannot solve the problem of irregularly causing the thickness deviation of the wafer polishing layer

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