Abstract: A curable underfill encapsulant composition that is applied directly onto semiconductor wafers before the wafers are diced into individual chips. The composition comprises a thermally curable resin system comprising an epoxy resin, a phenol-containing compound such as phenol or phenolic resin, a solvent, an imidazole phosphate salt catalyst, inorganic fillers, fluxing agents, and optionally, wetting agents. Various other additives, such as defoaming agents, adhesion promoters, flow additives and rheology modifiers may also be added as desired. The underfill encapsulant is B-stageable to provide a coating on the wafer that is smooth, non-tacky and will allow the wafer to be cleanly diced into individual chips. A method for producing an electronic package containing the B-stageable material may also utilize an unfilled liquid curable fluxing material on the substrate to which the chip is to be attached.

Abstract: A curable underfill encapsulant composition that is applied directly onto semiconductor wafers before the wafers are diced into individual chips. The composition comprises a thermally curable epoxy resin, a solvent, an imidazole-anhydride curing agent, fluxing agents, and optionally, wetting agents. Various other additives, such as defoaming agents, adhesion promoters, flow additives and rheology modifiers may also be added as desired. The underfill encapsulant is B-stageable to provide a coating on the wafer that is smooth, non-tacky and will allow the wafer to be cleanly diced into individual chips. A method for producing an electronic package containing the B-stageable material may also utilize an unfilled liquid curable fluxing material on the substrate to which the chip is to be attached.

Abstract: The present invention relates to a pressure sensitive fluxing underfill composition that may be pre-applied to electronic components, such as CSP's, in order to increase the reliability of the component against mechanical stresses such as impact and bending. The composition contains an epoxy resin, a solid anhydride curing agent, and catalyst. Other materials, such as air release agents and fillers, may also be added as desired. The composition may be applied selectively to parts of the CSP, for example to the solder bumps. The composition provides sufficient tack in order to hold the electronic assembly together during the assembly process.

Abstract: A silicon wafer has a B-stageable underfill material deposited on the active face of the wafer. The B-stageable underfill comprises a first composition with a lower curing temperature and a second composition with a higher curing temperature, characterized in that the first composition has been fully cured.

Abstract: The present invention relates to a pressure sensitive fluxing underfill composition that may be pre-applied to electronic components, such as CSP's, in order to increase the reliability of the component against mechanical stresses such as impact and bending. The composition contains an epoxy resin, a solid anhydride curing agent, and catalyst. Other materials, such as air release agents and fillers, may also be added as desired. The composition may be applied selectively to parts of the CSP, for example to the solder bumps. The composition provides sufficient tack in order to hold the electronic assembly together during the assembly process.

Abstract: A curable underfill encapsulant composition that is applied directly onto semiconductor wafers before the wafers are diced into individual chips. The composition comprises a thermally curable epoxy resin, a solvent, an imidazole-anhydride curing agent, fluxing agents, and optionally, wetting agents. Various other additives, such as defoaming agents, adhesion promoters, flow additives and rheology modifiers may also be added as desired. The underfill encapsulant is B-stageable to provide a coating on the wafer that is smooth, non-tacky and will allow the wafer to be cleanly diced into individual chips. A method for producing an electronic package containing the B-stageable material may also utilize an unfilled liquid curable fluxing material on the substrate to which the chip is to be attached.

Abstract: A curable underfill encapsulant composition that is applied directly onto semiconductor wafers before the wafers are diced into individual chips. The composition comprises a thermally curable resin system comprising an epoxy resin, a phenol-containing compound such as phenol or phenolic resin, a solvent, an imidazole-anhydride curing agent, inorganic fillers, fluxing agents, and optionally, wetting agents. Various other additives, such as defoaming agents, adhesion promoters, flow additives and rheology modifiers may also be added as desired. The underfill encapsulant is B-stageable to provide a coating on the wafer that is smooth, non-tacky and will allow the wafer to be cleanly diced into individual chips. A method for producing an electronic package containing the B-stageable material may also utilize an unfilled liquid curable fluxing material on the substrate to which the chip is to be attached.

Abstract: A curable underfill encapsulant composition which is especially useful in the no-flow encapsulation process. The composition contains a thermal curable resin system comprising an admixing of at least one epoxy resin and a phenol-containing compound such as phenol or phenolic resin, an imidazole-anhydride adduct as a catalyst, and a fluxing agent. Various additives, such as air release agents, flow additives, adhesion promoters and rheology modifiers may also be added as desired.

Abstract: A silicon wafer has a B-stageable underfill material deposited on the active face of the wafer. The B-stageable underfill comprises a first composition with a lower curing temperature and a second composition with a higher curing temperature, characterized in that the first composition has been fully cured.

Abstract: A curable composition for encapsulating an electronic component comprises one or more mono- or polyfunctional maleimide compounds, or one or more mono- or polyfunctional vinyl compounds other than maleimide compounds, or a combination of maleimide and vinyl compounds, with a free radical curing agent, and optionally, one or more fillers.

Abstract: An composition with improved electrical stability for use in microelectronic applications comprises a polymeric resin, a conductive filler, optionally either a reactive or a nonreactive diluent, optionally an inert filler, and an oxygen scavenger or corrosion inhibitor or both to provide the electrical stability. Alternatively, the composition may also include a low melting point metal filler component.

Abstract: A curable composition for encapsulating an electronic component comprises one or more mono- or polyfunctional maleimide compounds, or one or more mono- or polyfunctional vinyl compounds other than maleimide compounds, or a combination of maleimide and vinyl compounds, with a free radical curing agent, and optionally, one or more fillers.

Abstract: A curable composition for encapsulating an electronic component comprises one or more mono- or polyfunctional maleimide compounds, or one or more mono- or polyfunctional vinyl compounds other than maleimide compounds, or a combination of maleimide and vinyl compounds, with a free radical curing agent, and optionally, one or more fillers.

Abstract: A curable composition for use in the fabrication and assembly of circuit components and printed wire boards, which may be designed to be reworkable, comprises one or more mono- or polyfunctional maleimide compounds, or one or more mono- or polyfunctional vinyl compounds other than maleimide compounds, or a combination of maleimide and vinyl compounds, with a free-radical initiator or a photoinitiator, and optionally, one or more fillers. The circuit component is formed by applying the curable composition to the printed wire board and curing the composition in situ on the board.

Abstract: A method is disclosed for preparing an electronic assembly using a reworkable underfill encapsulant in which the encapsulant is cured in situ from a curable composition comprising one or more mono-functional maleimide compounds, or one or more mono-functional vinyl compounds other than maleimide compounds, or a combination of maleimide and vinyl compounds, a curing initiator and optionally, one or more fillers or adhesion promoters.

Abstract: A curable underfill encapsulant composition, suitable for use in semiconductor packaging, comprises one or more mono- or polyfunctional maleimide compounds, or one or more mono- or polyfunctional vinyl compounds other than maleimide compounds, or a combination of maleimide and vinyl compounds, with a free radical curing agent, and optionally, one or more fillers.

Abstract: A method is disclosed for preparing an electronic assembly using a reworkable underfill encapsulant in which the encapsulant is cured in situ from a curable composition comprising one or more mono-functional maleimide compounds, or one or more mono-functional vinyl compounds other than maleimide compounds, or a combination of maleimide and vinyl compounds, a curing initiator and optionally, one or more fillers or adhesion promoters.

Abstract: This invention relates to adhesive formulations, which can be snap-cured without loss of adhesive strength (as measured by die shear strength) and flexibility (as measured by radius of curvature), comprising 20-80 parts by weight of a flexible epoxy resin comprising an oligomeric backbone of alkylene or alkyleneoxy repeat units, terminated with an aromatic moiety bearing one or more epoxy functionalities, and 80-20 parts by weight of an aromatic O-glycidyl ether (to a total 100 parts), a curing catalyst, and optionally one or more fillers, and a phenolic hardener.

Abstract: This invention relates to adhesive formulations, which can be snap-cured without loss of adhesive strength (as measured by die shear strength) and flexibility (as measured by radius of curvature), comprising 20-80 parts by weight of a flexible epoxy resin and 80-20 parts by weight of an aromatic O-glycidyl ether (to a total 100 parts), a curing catalyst, and optionally one or more fillers.

Abstract: For use in microelectronics applications, an improvement to an epoxy resin composition to reduce bleeding of the composition when it is applied to a silicon or metal substrate consists in the addition to the composition of a polyhydroxyl compound having two or three hydroxyl groups, or of a monohydroxyl compound that also contains one or more phenyl groups. The hydroxyl compound is present in the composition in a ratio by weight to the flexibilizing compound of from 1:3 to 1:10.