Composition for polishing pad and polishing pad therewith

Abstract

An objective of the present invention is to provide a composition for polishing pad that is excellent in formability, abrasion resistance and small in temperature dependence of Young's modulus and a polishing pad therewith. The composition for polishing pad of the present invention comprises a water-insoluble matrix and a water-soluble particle dispersed in the water-insoluble matrix. The water-insoluble matrix contains a crosslinked ethylene-vinyl acetate copolymer and / or a crosslinked 1,2-polybutadiene and each of these is contained by a prescribed amount against the total of the water-insoluble matrix.

Description

[0001] 1. Field of the Invention[0002] The present invention relates to a composition for polishing pad and a polishing pad therewith. In more detail, the invention relates to a composition for polishing pad that is excellent in formability, abrasion resistance and small in temperature dependence of Young's modulus, and a polishing pad therewith. The present polishing pad is widely used in the production of semiconductor devices and is particularly preferable for the chemical mechanical polishing of a surface of a semiconductor wafer and the like.[0003] 2. Description of the Prior Art[0004] In recent years, the Chemical Mechanical Polishing (CMP) is attracting attention as a method of forming a flat surface for a substrate such as a wafer. In the CMP, a surface of a material to be polished is polished by sliding a polishing pad and the surface to be polished while supplying a slurry that is an aqueous dispersion in which abrasive is dispersed onto a surface of the polishing pad, and...

AI Technical Summary

Benefits of technology

[0165] The supporting layer is a layer that supports the polishing pad by the non-polishing surface side. The support layer is preferably softer than the polishing pad. When the polishing pad is provided with a softer support layer, even when a thickness of the polishing pad is thin (for instance, 0.5 mm or less), the polishing pad can be inhibited from peeling off the supporting layer or the polishing surface of the polishing pad can be inhibited from curving; resulting in stable polishing. The hardness of the supporting layer is preferably 90% or less of that of the polishing pad, more preferably 80% or less and particularly preferably 70% or less. The lower limit thereof is usually 10%. Furthermore, Shore D hardness of the supporting layer is preferably 70 or less, more preferably 60 or less and still more preferably 50 or less. The lower limit is usually 1.

Problems solved by technology

When the content of vinyl acetate unit is less than 3% by weight, the effect of reducing temperature dependence of the Young's modulus of the composition for polishing pad cannot be sufficiently obtained.

On the other hand, when the content of the vinyl acetate unit exceeds 50% by weight, an over-crosslinking tends to be caused, resulting in difficulty in retaining sufficient toughness in some cases.

Furthermore, the dissolution or the swelling may be caused not only by contact with water but also with an aqueous mixture medium containing an alcoholic solvent such as methanol.

On the other hand, when the average particle diameter exceeds 500 .mu.m, the magnitude of the pore to be formed becomes excessively large; as a result, a mechanical strength of the composition for polishing pad and a removal rate by the polishing part (polishing pad) obtained tend to reduce.

When the content of the water-soluble particle is less than 0.1% by volume, a pore may not be sufficiently formed on the polishing part (polishing pad) obtained cannot be not be sufficient, and the removal rate tends to reduce.

On the other hand, when the water-soluble particle is contained exceeding 90% by volume, it tends to be difficult to sufficiently inhibit the water-soluble particle present within the polishing part (polishing pad) from swelling or dissolving, and accordingly, it becomes difficult to maintain the hardness and the mechanical strength of the polishing part (polishing pad) at proper values.

When the content of uncrosslinked EVA is less than 10% by weight, the above effects after crosslinking treatment may not be sufficiently exhibited.

When the content of crosslinked PBD is less than 10% by weight, an effect due to an inclusion of crosslinked PBD may not be sufficiently exhibited.

When the content of the other crosslinked polymer is less than 5% by weight, the above effect may not be sufficiently exhibited.

When the elongation remaining after breaking exceeds 100%, fine fragments scraped or stretched out from a surface of the polishing pad during polishing or dressing unfavorably tend to clog the pores.

When the content of uncrosslinked PBD is less than 10% by weight, the above effects by crosslinking treatment may not be sufficiently exhibited.

When the content of the other crosslinkable polymer is 5% by weight or less, a resultant composition for polishing pad may be inferior in formability and abrasion resistance.

When the content of crosslinked EVA is less than 10% by weight, effects due to crosslinked EVA may not be sufficiently exhibited.

When the content of crosslinked PBD is less than 5% by weight, effects due to the inclusion thereof may not be sufficiently exhibited.

When the content of crosslinked PBD is less than 10% by weight, the above effects may not be sufficiently exhibited.

When the content of uncrosslinked EVA is less than 10% by weight, effects due to the inclusion thereof may not be sufficiently exhibited.

When the content of uncrosslinked PBD is less than 5% by weight, a content of a resultant crosslinked PBD may be little, and effects due to the inclusion thereof may not be sufficiently exhibited.

When the content of uncrosslinked PBD is less than 10% by weight, effects due to the inclusion thereof may not be sufficiently exhibited.

When the content of uncrosslinked EVA is less than 5% by weight, effects due to the inclusion thereof may not be sufficiently exhibited.

When the area is less than 50% of the above surface, a polishing effect may not be sufficiently exhibited.