A polishing pad dressing device

Abstract

The invention discloses a polishing pad dressing device, which comprises: a connecting arm extending horizontally; a dressing head unit arranged at one end of the connecting arm for dressing the polishing pad; a base unit arranged at the other end of the connecting arm and connected to the The arm is movably connected, and is used to drive the connecting arm to move vertically up and down with the trimming head unit, so that the trimming head unit approaches or moves away from the polishing pad in a vertical direction. The invention can stably realize the uniform and stable positive pressure in the dressing process, ensuring the consistency of the polishing and dressing process; it is not a motion amplification mechanism, and can effectively reduce the impact of the dressing head unit on the polishing pad during the process of moving to the polishing pad; No magnification, it is easier to ensure the consistency of the status of the trimming head unit.

Description

technical field [0001] The invention belongs to the field of semiconductor integrated circuit chip manufacturing equipment, and in particular relates to a polishing pad dressing device. Background technique [0002] In Chemical Mechanical Planarization (CMP) equipment, the wafer is polished on the surface of the rough polishing pad. As the polishing time prolongs, the surface of the polishing pad is ground and the polishing effect is lost. A diamond pad is required. The dresser of the grinding wheel trims the surface of the polishing pad, making the surface of the polishing pad rough and frictional, so that it can continue to have the function of polishing. [0003] In order to complete the entire polishing process, the polishing pad dresser needs to have a process close to the polishing pad in the height direction. At present, the UP / Down process of the polishing pad dresser is basically realized by the principle of the lever. One end of the moment arm is used to realize t...

AI Technical Summary

Problems solved by technology

[0004] This method has several defects: First, in the process of polishing pad wear, due to the change of the height of the polishing pad, the spatial angle α of the mechanical arm supporting the polishing pad dresser is a constantly changing process, in other words, the polishing The pressure direction F2 applied to the polishing pad by the pad dresser is constantly changing, which leads to the inability to guarantee the state of the polished polishing pad in a relatively stable state, and ultimately leads to the inability to guarantee the consistency of the polished wafer on the polishing pad; Secondly, due to the characteristics of the lever principle itself, the α angle is not zero in most cases, and the pressure applied to the polishing pad by the polishing pad dresser is not a positive pressure in most cases, that is, the polishing pressure in different areas of the polishing pad dresser is inconsistent, and The swing speed of the polishing pad dresser is limited during the working process, which leads to inconsistent dressing degrees in different areas of the polishing pad, that is, the consistency of the polishing pad shape cannot be guaranteed, which affects the consistency of the polished wafer; moreover, this The UP / Down implementation of the lever principle is actually a motion amplification mechanism, which amplifies the displacement of the power device to realize the movement of the polishing pad dresser head, but at the same time greatly reduces the spatial position stability of the polishing pad dresser, which is easy to The fluctuation of the power unit is doubled and then transmitted to the dressing head of the polishing pad dresser. The result is that the motion impact of the polishing pad dresser is amplified when the polishing pad dresser is close to the polishing pad, increasing the possibility of the polishing pad being damaged by the impact ;Finally, there is an UP / Down limit position of the polishing pad dresser during the UP / Down motion process, and a hard limit position needs to be set, and the error of the hard limit position in the process of processing, installation, and debugging will be amplified by the lever mechanism, thereby Cannot guarantee consistency of pad conditioner from station to station

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