Abstract: An electronic fabrication process and structure is provided for attaching discrete passive surface mount devices (SMD) to a substrate in a single step. A liquid noflow resin encapsulant containing flux material is dispensed between presoldered pads on a substrate. The SMD, having a pair of electrical contacts, is pressed into said encapsulant so that the electrical contacts make contact with said presoldered pads. Heat is applied to first activate said flux material and then reflow the solder on said presoldered pads to bond said SMD contacts to said presoldered pads. The reflow temperature is maintained for about 180 seconds during which time the resin solidifies. The resin encapsulant fills the space between substrate and SMD and forms fillets around the solder bonded contacts.

Abstract: A method and structure for coupling a semiconductor substrate (e.g., a semiconductor chip) to an organic substrate (e.g., a chip carrier). The coupling interfaces a solder member (e.g., a solder ball) to both a conductive pad on the semiconductor substrate and a conductive pad on the organic substrate. Thermal strains on the solder member during thermal cycling may be reduced by having a surface area of the pad on the semiconductor substrate exceed a surface area of the pad on the organic substrate. Thermal strains on the solder member during thermal cycling may also be reduced by having a distance from a centerline of the solder member to a closest lateral edge of the semiconductor substrate exceed about 0.25 mm.

Abstract: An electronic fabrication process and structure is provided for attaching discrete passive surface mount devices (SMD) to a substrate in a single step. A liquid noflow resin encapsulant containing flux material is dispensed between presoldered pads on a substrate. The SMD, having a pair of electrical contacts, is pressed into said encapsulant so that the electrical contacts make contact with said presoldered pads. Heat is applied to first activate said flux material and then reflow the solder on said presoldered pads to bond said SMD contacts to said presoldered pads. The reflow temperature is maintained for about 180 seconds during which time the resin solidifies. The resin encapsulant fills the space between substrate and SMD and forms fillets around the solder bonded contacts.

Abstract: A method and structure for coupling a semiconductor substrate (e.g., a semiconductor chip) to an organic substrate (e.g., a chip carrier). The coupling interfaces a solder member (e.g., a solder ball) to both a conductive pad on the semiconductor substrate and a conductive pad on the organic substrate. Thermal strains on the solder member during thermal cycling may be reduced by having a surface area of the pad on the semiconductor substrate exceed a surface area of the pad on the organic substrate. Thermal strains on the solder member during thermal cycling may also be reduced by having a distance from a centerline of the solder member to a closest lateral edge of the semiconductor substrate exceed about 0.25 mm.

Abstract: An electronic fabrication process and structure is provided for attaching discrete passive surface mount devices (SMD) to a substrate in a single step. A liquid noflow resin encapsulant containing flux material is dispensed between presoldered pads on a substrate. The SMD, having a pair of electrical contacts, is pressed into said encapsulant so that the electrical contacts make contact with said presoldered pads. Heat is applied to first activate said flux material and then reflow the solder on said presoldered pads to bond said SMD contacts to said presoldered pads. The reflow temperature is maintained for about 180 seconds during which time the resin solidifies. The resin encapsulant fills the space between substrate and SMD and forms fillets around the solder bonded contacts.

Abstract: Reworkable thermally conductive adhesive composition including a cured reaction product from a diepoxide wherein the epoxy groups are connected through an acyclic acetal moiety, a cyclic anhydride and a thermally conductive filler are provided and used to bond semiconductive devices to a chip carrier or heat spreader.

Abstract: An electronic fabrication process and structure is provided for attaching discrete passive surface mount devices (SMD) to a substrate in a single step. A liquid noflow resin encapsulant containing flux material is dispensed between presoldered pads on a substrate. The SMD, having a pair of electrical contacts, is pressed into said encapsulant so that the electrical contacts make contact with said presoldered pads. Heat is applied to first activate said flux material and then reflow the solder on said presoldered pads to bond said SMD contacts to said presoldered pads. The reflow temperature is maintained for about 180 seconds during which time the resin solidifies. The resin encapsulant fills the space between substrate and SMD and forms fillets around the solder bonded contacts.

Abstract: An electronic module having enhanced adhesion at the chip passivation and underfill interface is disclosed. The surface of the chip passivation is chemically modified to a sufficient depth such that the cured passivation is more reactive. The modified surface is treated with a polyamine preferably having a cyclic amine group extending from a preferably aliphatic backbone. During reflow of the solder joints of the electronic module by heating, the modified passivation reacts with the polyamine at the amine functionality. Following underfill of the electronic module with a polymeric material, preferably an epoxy resin, the polyamine on the surface of the passivation reacts with the underfill material during curing of the underfill material. The resulting electronic module is more robust since the amine acts as a chemical anchoring site for both the modified passivation and the underfill material.

Abstract: Reworkable thermally conductive adhesive composition comprising a cured reaction product from a diepoxide wherein the epoxy groups are connected through an acyclic acetal moiety, a cyclic anhydride and a thermally conductive filler are provided and used to bond semiconductive devices to a chip carrier or heat spreader.

Abstract: An electronic fabrication process and structure is provided for attaching discrete passive surface mount devices (SMD) to a substrate in a single step. A liquid noflow resin encapsulant containing flux material is dispensed between presoldered pads on a substrate. The SMD, having a pair of electrical contacts, is pressed into said encapsulant so that the electrical contacts make contact with said presoldered pads. Heat is applied to first activate said flux material and then reflow the solder on said presoldered pads to bond said SMD contacts to said presoldered pads. The reflow temperature is maintained for about 180 seconds during which time the resin solidifies. The resin encapsulant fills the space between substrate and SMD and forms fillets around the solder bonded contacts.

Abstract: An electronic module having enhanced adhesion at the chip passivation and underfill interface is disclosed. The surface of the chip passivation is chemically modified to a sufficient depth such that the cured passivation is more reactive. The modified surface is treated with a polyamine preferably having a cyclic amine group extending from a preferably aliphatic backbone. During reflow of the solder joints of the electronic module by heating, the modified passivation reacts with the polyamine at the amine functionality. Following underfill of the electronic module with a polymeric material, preferably an epoxy resin, the polyamine on the surface of the passivation reacts with the underfill material during curing of the underfill material. The resulting electronic module is more robust since the amine acts as a chemical anchoring site for both the modified passivation and the underfill material.

Abstract: Reworkable thermally conductive adhesive composition comprising a cured reaction product from a diepoxide wherein the epoxy groups are connected through an acyclic acetal moiety, a cyclic anhydride and a thermally conductive filler are provided and used to bond semiconductive devices to a chip carrier or heat spreader.

Abstract: An electronic module having enhanced adhesion at the chip passivation and underfill interface is disclosed. The surface of the chip passivation is chemically modified to a sufficient depth such that the cured passivation is more reactive. The modified surface is treated with a polyamine preferably having a cyclic amine group extending from a preferably aliphatic backbone. During reflow of the solder joints of the electronic module by heating, the modified passivation reacts with the polyamine at the amine functionality. Following underfill of the electronic module with a polymeric material, preferably an epoxy resin, the polyamine on the surface of the passivation reacts with the underfill material during curing of the underfill material. The resulting electronic module is more robust since the amine acts as a chemical anchoring site for both the modified passivation and the underfill material.

Abstract: An encapsulated semiconductor chip module. The chip module has the overlying encapsulant adhered directly and integrally to bare portions of the substrate to which the chip is mounted. This configuration enhances the adhesion and inhibits unintended delamination of the encapsulant from the balance of the module. The module is made by patterning anchor openings into the solder mask. The anchor openings expose corresponding portions of the substrate. It is important to locate the anchor openings over parts of the substrate that do not have circuitry on them, that is, on bare portions, so as to avoid corrosion or contamination of the circuit connections.

Abstract: A method and structure for coupling a semiconductor substrate (e.g., a semiconductor chip) to an organic substrate (e.g., a chip carrier). The coupling interfaces a solder member (e.g., a solder ball) to both a conductive pad on the semiconductor substrate and a conductive pad on the organic substrate. Thermal strains on the solder member during thermal cycling may be reduced by having a surface area of the pad on the semiconductor substrate exceed a surface area of the pad on the organic substrate. Thermal strains on the solder member during thermal cycling may also be reduced by having a distance from a centerline of the solder member to a closest lateral edge of the semiconductor substrate exceed about 0.25 mm.

Abstract: Reworkable thermally conductive adhesive composition comprising a cured reaction product from a diepoxide wherein the epoxy groups are connected through an acyclic acetal moiety, a cyclic anhydride and a thermally conductive filler are provided and used to bond semiconductive devices to a chip carrier or heat spreader.

Abstract: A method for forming a flip-chip-on-board assembly. An integrated circuit (IC) chip having a polyimide passivation layer is joined to a chip carrier via a plurality of solder bumps which electrically connect a plurality of contact pads on the IC chip to corresponding contacts on the chip carrier. A space is formed between a surface of the passivation layer and a surface of the chip carrier. A plasma is applied, to chemically modify the surface of the chip carrier and the passivation layer of the IC chip substantially without roughening the surface of the passivation layer. The plasma is either an O2 plasma or a microwave-generated Ar and N2O plasma. An underfill encapsulant material is applied to fill the space. The plasma treatment may be performed after the step of joining. Then, the chip and chip carrier are treated with the plasma simultaneously. Alternatively, the IC chip and chip carrier may be treated with the plasma before they are joined to one another.

Abstract: A method for forming a flip-chip-on-board assembly. An integrated circuit (IC) chip having a polyimide passivation layer is joined to a chip carrier via a plurality of solder bumps which electrically connect a plurality of contact pads on the IC chip to corresponding contacts on the chip carrier. A space is formed between a surface of the passivation layer and a surface of the chip carrier. A plasma is applied, to chemically modify the surface of the chip carrier and the passivation layer of the IC chip substantially without roughening the surface of the passivation layer. The plasma is either an O2 plasma or a microwave-generated Ar and N2O plasma. An underfill encapsulant material is applied to fill the space. The plasma treatment may be performed after the step of joining. Then, the chip and chip carrier are treated with the plasma simultaneously. Alternatively, the IC chip and chip carrier may be treat with the plasma before they are joined to one another.

Abstract: An encapsulated semiconductor chip module. The chip module has the overlying encapsulant adhered directly and integrally to bare portions of the substrate to which the chip is mounted. This configuration enhances the adhesion and inhibits unintended delamination of the encapsulant from the balance of the module. The module is made by patterning anchor openings into the solder mask. The anchor openings expose corresponding portions of the substrate. It is important to locate the anchor openings over parts of the substrate that do not have circuitry on them, that is, on bare portions, so as to avoid corrosion or contamination of the circuit connections.

Abstract: An electronic module having enhanced adhesion at the chip passivation and underfill interface is disclosed. The surface of the chip passivation is chemically modified to a sufficient depth such that the cured passivation is more reactive. The modified surface is treated with a polyamine preferably having a cyclic amine group extending from a preferably aliphatic backbone. During reflow of the solder joints of the electronic module by heating, the modified passivation reacts with the polyamine at the amine functionality. Following underfill of the electronic module with a polymeric material, preferably an epoxy resin, the polyamine on the surface of the passivation reacts with the underfill material during curing of the underfill material. The resulting electronic module is more robust since the amine acts as a chemical anchoring site for both the modified passivation and the underfill material.