Toyo Tire Rubber Co., Ltd.

Shigeru Komai

Koichi A Ono

Tetsuo Shimomura

Takatoshi Yamada

Masahiko Nakamori

Masayuki Tsutsumi

Kazuyuki Ogawa

Atsushi Kazuno

Tsuyoshi Kimura

Takashi Masui

Hiroshi Seyanagi

The invention provides a polishing pad by which optical materials such as lenses, reflecting mirrors etc., or materials requiring a high degree of surface planarity, as in the polishing of silicone wafers, glass substrates or aluminum substrates for hard disks, or general metal polishing, can be flattened with stability and high polishing efficiency. The invention also provides a polishing pad for semiconductor wafers, which is superior in planarizing characteristic, is free from scratches and can be produced at low cost. There is provided a polishing pad which is free from dechucking error so that neither damage to wafers nor decrease in operating efficiency occurs. There is provided a polishing pad which is satisfactory in planarity, within wafer uniformity, and polishing rate and produces less change in polishing rate. There is provided a polishing pad which can make planarity improvement and scratch decrease compatible.

Polishing pad and method of producing the same

A polishing pad includes a polishing layer having abrasive grains dispersed in a resin and is characterized in that the resin is a resin containing ionic groups in the range of 20 to 1500 eq/ton.

Polishing pad and cushion layer for polishing pad

Grinding pad and method of producing the same

A polishing pad includes at least a polishing layer and a cushion layer and is characterized in that the difference in hardness in Shore D hardness between the polishing layer and the cushion layer is 3 or more.

A method of producing a polishing pad having a polishing layer is characterized in that the polishing layer is produced by a photolithographic method including: forming a sheet molding from a curing composition containing at least an initiator and an energy ray-reactive compound to be cured with energy rays; exposing the sheet molding to energy rays to induce modification thereof, to change the solubility of the sheet molding in a solvent; and developing the sheet molding after irradiation with energy rays, to partially remove the curing composition with a solvent thereby forming a concave and convex pattern at least one surface.

Method of producing polishing pad

The polishing pad of this invention is a polishing pad effecting stable planarizing processing, at high polishing rate, materials requiring surface flatness at high level, such as a silicon wafer for semiconductor devices, a magnetic disk, an optical lens etc. This invention provides a polishing pad which can be subjected to surface processing to form a sheet or grooves, is excellent in thickness accuracy, attains a high polishing rate, achieves a uniform polishing rate, and also provides a polishing pad which is free of quality variations resulting from an individual variation, easily enables a change the surface patterns, enables fine surface pattern, is compatible with various materials to be polished, is free of burrs upon forming the pattern. This invention provides a polishing pad which can have abrasive grains mixed at very high density without using slurry, and generates few scratches by preventing aggregation of abrasive grains dispersed therein. The polishing pad of this invention has a polishing layer formed from a curing composition to be cured with energy rays, the polishing layer being formed surface pattern thereon by photolithography. The polishing pad of this invention comprises a polishing layer resin having abrasive grains dispersed therein, the resin containing ionic groups in the range of 20 to 1500 eq/ton.

Growing community of inventors

Ohtsu, Japan

Shigeru Komai