Adhesive composition, adhesive sheet, and back grinding method for semiconductor wafer

A pressure-sensitive adhesive sheet for a protective film for semiconductor wafer backgrinding, which comprises:

• a base film;
• and
• a pressure-sensitive adhesive layer on one or both sides of the base film,
• wherein the pressure-sensitive adhesive layer contains a cured product of a pressure-sensitive adhesive composition,
• wherein the pressure-sensitive adhesive composition comprises a polymer of a monomer mixture,
• wherein the monomer mixture comprises (meth)acrylic acid ester monomer mixture including 1 to 30 parts by weight of isobornyl (meth)acrylate and 60 to 98.9 parts by weight of (meth)acrylic acid ester monomer other than the isobornyl (meth)acrylate;
• and a crosslinkable monomer including a hydroxy group or a carboxyl group,
• wherein the polymer comprises only the hydroxy group or the carboxyl group as a crosslinkable functional group and
• wherein the polymer has a glass transition temperature of −50° C. to 15° C.

A pressure-sensitive adhesive sheet for a protective film for semiconductor wafer backgrinding, which comprises:

• a base film;
• and
• a pressure-sensitive adhesive layer on one or both sides of the base film,
• wherein the pressure-sensitive adhesive layer contains a cured product of a pressure-sensitive adhesive composition,
• wherein the pressure-sensitive adhesive composition comprises a polymer of a monomer mixture,
• wherein the monomer mixture comprises (meth)acrylic acid ester monomer mixture including 1 to 30 parts by weight of isobornyl (meth)acrylate and 60 to 98.9 parts by weight of (meth)acrylic acid ester monomer other than the isobornyl (meth)acrylate;
• and a crosslinkable monomer including a hydroxy group or a carboxyl group,
• wherein the pressure-sensitive adhesive composition further comprises a crosslinking agent forming a crosslinking structure only by a thermal curing process, wherein the pressure-sensitive adhesive layer comprises only a crosslinking structure formed by only the polymer and the crosslinking agent and
• wherein the polymer has a glass transition temperature of −50° C. to 15° C.

A pressure-sensitive adhesive sheet for a protective film for semiconductor wafer backgrinding, which comprises:

• a base film;
• and
• a pressure-sensitive adhesive layer on one or both sides of the base film,
• wherein the pressure-sensitive adhesive layer contains a cured product of a pressure-sensitive adhesive composition,
• wherein the pressure-sensitive adhesive composition comprises a polymer of a monomer mixture,
• wherein the monomer mixture consists of (meth)acrylic acid alkyl ester monomer mixture consisting of 1 to 30 parts by weight of isobornyl (meth)acrylate and 60 to 98.9 parts by weight of (meth)acrylic acid alkyl ester monomer other than the isobornyl (meth)acrylate;
• and a crosslinkable monomer including a hydroxy group or a carboxyl group,
• wherein the pressure-sensitive adhesive composition further comprises a crosslinking agent forming a crosslinking structure only by a thermal curing process, wherein the polymer comprises only the hydroxy group or the carboxyl group as a crosslinkable functional group, wherein the pressure-sensitive adhesive layer comprises only a crosslinking structure formed by only the polymer and the crosslinking agent and
• wherein the polymer has a glass transition temperature of −50° C. to 15° C.