Patent ID: 6666752
Filing Date: 2003-12-23
Classification: B24B,C08L,C09J,H01L

Abstract:
A wafer retainer comprising:a foam layer capable of adsorbing a wafer on a surface thereof in a detachable manner; a first pressure-sensitive adhesive layer formed on a back face of the foam layer; a support formed on a back face of the first pressure-sensitive adhesive layer; a second pressure-sensitive adhesive layer formed on a back face of the support for adhering to a base plate of a polishing machine; and a release sheet releasably attached to the second pressure-sensitive adhesive layer, wherein the second pressure-sensitive adhesive layer comprises an adhesive composition, the adhesive composition containing a pressure-sensitive adhesive and a side-chain crystallizable polymer so that the side-chain crystallizable polymer is present in an amount of about 1% to about 30% by weight based on the adhesive composition, and the side-chain crystallizable polymer including as a main component thereof an acrylic acid ester and/or methacrylic acid ester which has a straight-chain alkyl group including 16 or more carbon atoms as a side chain, wherein the adhesive composition contains a tackifier in an amount of about 10% to about 30% by weight, wherein the side-chain crystallizable polymer has a molecular weight of about 2,000 to about 15,000, and wherein adhesiveness of the adhesive composition, measured by a peeling force, is decreased by more than about 90% when heated above about 50Â° C., with respect to the adhesiveness when measured at 23Â° C.