Integrated grinding pad and its mfg. method

Abstract

An integral polishing pad includes an elastic support layer and a polishing layer, which is formed on the elastic support layer and has a higher hardness than the elastic support layer. The elastic support layer and the polishing layer are made from materials chemically compatible with each other so that a structural border between the elastic support layer and the polishing layer does not exist. In addition, the integral polishing pad also includes a transparent region, which is transparent to a light source used to detect the surface state of an object being polished and integrated with the other elements of the integral polishing pad. The integral polishing pad has high planarization efficiency and uniform properties, and thus can be reliably used for polishing. In addition, the integral polishing pad prevents a congestion of a polishing slurry and facilitates delivery of the polishing slurry. The integral polishing pad does not need an adhesive for connecting elements or a process for bonding the elements, thereby simplifying manufacturing processes.

Description

technical field [0001] The present invention relates to a polishing pad and a manufacturing method thereof, in particular to a polishing pad in which an elastic support layer and a polishing layer are integrated and a manufacturing method thereof. Background technique [0002] With the high integration and miniaturization of semiconductors and the multi-layered wiring structure, in the chemical mechanical polishing process introduced for the overall planarization of semiconductor elements, the polishing speed and planarization speed are more important, and these depend on Engineering conditions of grinding equipment, types of grinding liquid, types of pads, etc. In particular, the polishing pad, which is in direct contact with the wafer in the polishing process and is a consumable part, functions as an important factor determining the performance of the polishing process. [0003] U.S. Patent No. 5,257,478 discloses a polishing pad that elastically compresses and expands th...

AI Technical Summary

Problems solved by technology

However, the polishing pad of U.S. Patent No. 5,605,760 requires a process of punching the pad and then installing the transparent window in the pad in order to form a transparent window through which light beams can pass, making the manufacturing process complicated.

And, in the polishing process, the movement and delivery of the abrasive slurry are hindered by the gaps in the connection between the transparent window and the pad, and at the same time, the slurry deposited in the gaps becomes agglomerated, which may cause scratches on the surface of the wafer. mark

In addition, since the substance of the transparent window and the remaining part of the pad are different, scratches may be generated centering on the transparent window during the polishing process.

In U.S. Patent No. 6,171,181, there is disclosed a polishing pad that forms a transparent part in the pad by cooling a certain part in the mold more rapidly than other parts, but if such a polishing pad is to be manufactured, it can be adjusted as needed. Special molds for different temperatures, so the cost will increase

Also, for the pads disclosed in U.S. Patent No. 5,605,760 and U.S. Patent No. 6,171,181, since the hysteresis loss cannot be minimized, an elastic support layer is also required, for which reason it is also necessary to form a transparent window or The transparent part complicates the manufacturing process of the polishing pad

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