Abstract: Methods for forming flip chip interconnection, in which the bump interconnect is defined at least in part by an underfill. The underfill includes a material that is thermally cured; that is, raising the temperature of the underfill material can result in progressive curing of the underfill through stages including a gel stage and a fully cured stage. According to the invention, during at least an early stage in the process the semiconductor chip is carried by a thermode, which is employed to control the temperature of the assembly in a specified way. Also, flip chip interconnections and flip chip packages made according to the methods of invention.

Abstract: A wire bond interconnection between a die pad and a bond finger includes a support pedestal at a bond site of the lead finger, a ball bond on the die pad, and a stitch bond on the support pedestal, in which a width of the lead finger at the bond site is less than a diameter of the support pedestal. Also, a semiconductor package including a die mounted onto and electrically connected by a plurality of wire bonds to a substrate, in which each of the wire bonds includes a wire ball bonded to a pad on the die and stitch bonded to a support pedestal on a bond site on a lead finger, and in which the width of the lead finger at the bond site is less than the diameter of the support pedestal.

Abstract: An integrated circuit package system comprising: forming an area array substrate; mounting surface conductors on the area array substrate; forming a molded package body on the area array substrate and the surface conductors; providing a step in the molded package body; and exposing a surface conductor by the step.

Abstract: An integrated circuit package system comprising: providing a package substrate; attaching an integrated circuit die over the package substrate wherein the integrated circuit die has a mount height; attaching an attachment structure having a height substantially the same as the mount height and planar dimensions predetermined to fit adjacent the integrated circuit die and over the package substrate; and attaching a heat dissipation device over the integrated circuit die and the attachment structure.

Abstract: A flip chip interconnect is made by mating the interconnect bump directly onto a lead, rather than onto a capture pad. Also, a flip chip package includes a die having solder bumps attached to interconnect pads in an active surface, and a substrate having electrically conductive traces in a die attach surface, in which the bumps are mated directly onto the traces. In some embodiments the interconnection is formed without employing a solder mask. In some methods a curable adhesive is dispensed either onto the bumps on the die or onto the traces on the substrate; the adhesive is partly cured during the mating process, and the partly cured adhesive serves to confine the molten solder during a reflow process.

Abstract: A stud bump structure for electrical interconnection between a pair of members includes a base portion, and a stem portion. The base portion is affixed to a pad or trace in one of the pair of members to be interconnected (such as an integrated circuit chip), and the stem end is configured to contact a metal pad on the other member (such as a printed circuit board) to complete the interconnect. According to the invention, the stem end is truncated to form a transverse plane, and the stem is more compliant than the base. Also, a method for forming a stud bump on a contact surface, includes forming a bump base portion on the surface, drawing out a generally conical tail from a top of the base, and truncating the tail to form a stem portion having a planar transverse top surface and having a length from the top of the base portion to the top surface. In some embodiments the tail portion, at least, of the stud bump is formed using a wire bonding tool.

Abstract: A semiconductor package comprises a base substrate with a semiconductor die mounted on a top side of the base substrate and an interposer substrate mounted on top of the die. The bottom side of the interposer substrate can be electrically coupled to the top side of the base substrate through vertical connectors. The top side of the interposer substrate is substantially exposed and comprises input/output (I/O) terminals for the mounting of additional electronic components. The base and interposer substrates can be configured with I/O terminals such that components mounted on the substrates can be electrically coupled through the vertical connectors. The base substrate also can be electrically coupled to an additional electronic component, such as a printed circuit board. Electrical connections can be “wrapped around” from the base substrate to the top of the interposer substrate.

Abstract: A method for encapsulating flip chip interconnects includes applying a limited quantity of encapsulating resin to the interconnect side of an integrated circuit chip, and thereafter bringing the chip together with a substrate under conditions that promote the bonding of bumps on the interconnect side of the chip with bonding pads on the substrate. In some embodiments, the step of applying resin to the chip includes dipping the interconnect side of the chip to a predetermined depth in a pool of resin, and then withdrawing the chip from the resin pool. In some embodiments the step of applying resin to the chip includes providing a reservoir having a bottom, providing a pool of resin in the reservoir to a shallow depth over the reservoir bottom, dipping the chip into the resin pool so that the bumps contact the reservoir bottom, and then withdrawing the chip from the resin pool.

Abstract: A wire bond interconnection between a die pad and a bond finger includes a support pedestal at a bond site of the lead finger, a ball bond on the die pad, and a stitch bond on the support pedestal, in which a width of the lead finger at the bond site is less than a diameter of the support pedestal. Also, a semiconductor package including a die mounted onto and electrically connected by a plurality of wire bonds to a substrate, in which each of the wire bonds includes a wire ball bonded to a pad on the die and stitch bonded to a support pedestal on a bond site on a lead finger, and in which the width of the lead finger at the bond site is less than the diameter of the support pedestal. Also, such a package in which the package substrate includes a two-tier substrate, each tier including a plurality of lead fingers having a lead finger bond pitch about twice the die pad pitch, the lead fingers of the first tier and the second tier having a staggered arrangement.

Abstract: Methods are disclosed for electrically connecting I/O bond-pads on a chip to corresponding I/O bond-pads on a substrate. In an exemplary method a respective stud-bump is formed on each I/O bond-pad on the substrate. The stud-bumps can be made of a fusible material, or a layer of fusible material can be formed on each I/O bond-pad on the chip. The chip is flipped and placed on the stud-bumps such that the I/O bond-pads on the chip are registered with the corresponding stud-bumps on the substrate. At each stud-bump, the fusible material is caused to fuse with and electrically connect the respective stud-bump to the respective I/O bond-pad on the chip. The method can include forming under-bump metallization (UBM) on each of the I/O bond-pads on the chip before placing the chip on the stud-bumps. The resulting structures provide robust I/O connections and can be fabricated using fewer process steps and using process steps that are compatible with other processes in wafer-fabrication and chip-assembly facilities.

Abstract: An integrated circuit package system includes providing a substrate having a bond finger thereon and forming a pedestal on a portion of the bond finger. A first die is mounted on the substrate and adjacent to the bond finger. A portion of the first die, a portion of the bond finger, and a portion of the pedestal are embedded in an resin layer with an exposed portion of the pedestal protruding from the resin layer. A second die is mounted on the first die and electrically coupled to the exposed portion of the pedestal.

Abstract: A semiconductor package having an embedded die and solid vertical interconnections, such as stud bump interconnections, for increased integration in the direction of the z-axis (i.e., in a direction normal to the circuit side of the die). The semiconductor package can include a die mounted in a face-up configuration (similar to a wire bond package) or in a face-down or flip chip configuration.

Abstract: A flip chip interconnect pad layout has the die signal pads are arranged on the die surface near the perimeter of the die, and the die power and ground pads arranged on the die surface inboard from the signal pads; and has the signal pads on the corresponding package substrate arranged in a manner complementary to the die pad layout and the signal lines routed from the signal pads beneath the die edge away from the die footprint, and has the power and ground lines routed to vias beneath the die footprint. Also, a flip chip semiconductor package in which the flip chip interconnect pad layouts have the die signal pads situated in the marginal part of the die and the die power and ground pads arranged on the die surface inboard from the signal pads, and the corresponding package substrates have signal pads arranged in a manner complementary to the die pad layout and signal lines routed from the signal pads beneath the die edge away from the die footprint.

Abstract: A solder bump reflow process includes raising the temperature of an aligned die-substrate assembly to a temperature and for a time sufficient to cause a first reflow; allowing the temperature of the assembly to fall to a first cooling temperature and for a time sufficient to re-solidify the solder; raising the temperature of the die-substrate assembly a second time to a temperature and for a time sufficient to cause a second reflow; allowing the temperature of the assembly to fall a second time to a second cooling temperature and eventually to an ambient room temperature; in which at least the first and second melts and the first re-solidification are conducted without exposing the assembly to oxidizing atmosphere. Also, apparatus for carrying out the method includes a multi-zone oven.

Abstract: A flip chip interconnect is made by mating the interconnect bump directly onto a lead, rather than onto a capture pad. Also, a flip chip package includes a die having solder bumps attached to interconnect pads in an active surface, and a substrate having electrically conductive traces in a die attach surface, in which the bumps are mated directly onto the traces. In some embodiments the interconnection is formed without employing a solder mask. In some methods a curable adhesive is dispensed either onto the bumps on the die or onto the traces on the substrate; the adhesive is partly cured during the mating process, and the partly cured adhesive serves to confine the molten solder during a reflow process.

Abstract: An integrated circuit package system includes providing a substrate having a bond finger thereon and forming a pedestal on a portion of the bond finger. A first die is mounted on the substrate and adjacent to the bond finger. A portion of the first die, a portion of the bond finger, and a portion of the pedestal are embedded in an resin layer with an exposed portion of the pedestal protruding from the resin layer. A second die is mounted on the first die and electrically coupled to the exposed portion of the pedestal.

Abstract: An integrated circuit mount system includes an integrated circuit, a solder mask for the integrated circuit, and a solder mask pad on the substrate with the solder mask.

Abstract: A package-on-package system is provided with a base package. Solder caps are provided on the top of the base package. The solder caps are configured to protrude above subsequent resin bleed, and are configured for merging with solder balls of a top package to form larger solder balls between such a top package and the base package.

Abstract: A solder bump confinement system is provided including providing a substrate, patterning a contact material on the substrate, depositing an inner passivation layer over the contact material and the substrate, forming an under bump material defining layer over the contact material by sputtering, and forming a system interconnect over the contact material and on the under bump material defining layer.

Abstract: A stud bump structure for electrical interconnection between a pair of members includes a base portion, and a stem portion. The base portion is affixed to a pad or trace in one of the pair of members to be interconnected (such as an integrated circuit chip), and the stem end is configured to contact a metal pad on the other member (such as a printed circuit board) to complete the interconnect. According to the invention, the stem end is truncated to form a transverse plane, and the stem is more compliant than the base. Also, a method for forming a stud bump on a contact surface, includes forming a bump base portion on the surface, drawing out a generally conical tail from a top of the base, and truncating the tail to form a stem portion having a planar transverse top surface and having a length from the top of the base portion to the top surface. In some embodiments the tail portion, at least, of the stud bump is formed using a wire bonding tool.