Combinations of resin compositions and methods of use thereof

An underfill composition comprising

• a first curable transparent resin composition comprising at least one aromatic epoxy resin in combination with at least one solvent, a functionalized colloidal silica dispersion having a particle size of about 50 nm to about 100 nm, and at least one additional component selected from the group consisting of cycloaliphatic epoxy monomers, aliphatic epoxy monomers, hydroxy aromatic compounds, and combinations and mixtures thereof;
• and
• a second curable fluxing composition comprising at least one epoxy resin in combination with at least one epoxy hardener,
• wherein the at least one epoxy hardener comprises a difunctional siloxane anhydride of the formula:
• where X is from 0 to 50 inclusive, and each R′ and R″ are independently selected from the group consisting of C1-22 alkyl, C1-22 alkoxy, C2-22 alkenyl, C6-14 aryl, C6-22 alkyl-substituted aryl, and C6-22 arylalkyl.

An underfill composition comprising

• a first curable transparent epoxy resin comprising a cresol novolac epoxy resin in combination with at least one solvent, a functionalized colloidal silica dispersion having a particle size of about 50 nm to about 100 nm, and at least one additional component selected from the group consisting of cycloaliphatic epoxy monomers, aliphatic epoxy monomers, hydroxy aromatic compounds, and combinations and mixtures thereof;
• and
• a second curable fluxing composition comprising at least one epoxy resin in combination with at least one difunctional siloxane anhydride epoxy hardener of the formula:
• where X is from 0 to 50 inclusive, and each R′ and R″ are independently selected from the group consisting of C1-22 alkyl, C1-22 alkoxy, C2-22 alkenyl, C6-14 aryl, C6-22 alkyl-substituted aryl, and C6-22 arylalkyl.

A solid state device comprising:

• a chip;
• a substrate;
• and
• an underfill composition between the chip and the substrate comprising a first curable transparent resin composition comprising at least one aromatic epoxy resin in combination with at least one solvent, a functionalized colloidal silica dispersion having a particle size of about 50 nm to about 100 nm, and at least one additional component selected from the group consisting of cycloaliphatic epoxy monomers, aliphatic epoxy monomers, hydroxy aromatic compounds and combinations and mixtures thereof;
• and
• a second curable fluxing composition comprising at least one epoxy resin in combination with at least one epoxy hardener,
• wherein the at least one epoxy hardener comprises a difunctional siloxane anhydride epoxy hardener of the formula:
• where X is from 0 to 50 inclusive, and each R′ and R″ are independently selected from the group consisting of C1-22 alkyl, C1-22 alkoxy, C2-22 alkenyl, C6-14 aryl, C6-22 alkyl-substituted aryl, and C6-22 arylalkyl.

A method for producing a solid state device comprising:

• applying to a chip a first curable transparent resin composition comprising an aromatic epoxy resin in combination with a solvent, a functionalized colloidal silica dispersion, and at least one other component selected from the group consisting of cycloaliphatic epoxy monomers, aliphatic epoxy monomers, hydroxy aromatic compounds and combinations and mixtures thereof, to produce a coated chip;
• applying a second curable fluxing composition comprising at least one epoxy resin in combination with at least one epoxy hardener to a substrate;
• placing the coated chip on a portion of the substrate to which the fluxing composition has been applied;
• and
• curing the first curable transparent resin composition and second curable fluxing composition to form an underfill composition.