A package structure includes a chip attached to a substrate. The chip includes a bump structure including a conductive pillar having a length (L) measured along a long axis of the conductive pillar and a width (W) measured along a short axis of the conductive pillar. The substrate includes a pad region and a mask layer overlying the pad region, wherein the mask layer has an opening exposing a portion of the pad region. The chip is attached to the substrate to form an interconnection between the conductive pillar and the pad region. The opening has a first dimension (d1) measured along the long axis and a second dimension (d2) measured along the short axis. In an embodiment, L is greater than d1, and W is less than d2.

A semiconductor device has a semiconductor die with a die pad layout. Signal pads in the die pad layout are located primarily near a perimeter of the semiconductor die, and power pads and ground pads are located primarily inboard from the signal pads. The signal pads are arranged in a peripheral row or in a peripheral array generally parallel to an edge of the semiconductor die. Bumps are formed over the signal pads, power pads, and ground pads. The bumps can have a fusible portion and non-fusible portion. Conductive traces with interconnect sites are formed over a substrate. The bumps are wider than the interconnect sites. The bumps are bonded to the interconnect sites so that the bumps cover a top surface and side surfaces of the interconnect sites. An encapsulant is deposited around the bumps between the semiconductor die and substrate.

A semiconductor device has a semiconductor die with a die pad layout. Signal pads in the die pad layout are located primarily near a perimeter of the semiconductor die, and power pads and ground pads are located primarily inboard from the signal pads. The signal pads are arranged in a peripheral row or in a peripheral array generally parallel to an edge of the semiconductor die. Bumps are formed over the signal pads, power pads, and ground pads. The bumps can have a fusible portion and non-fusible portion. Conductive traces with interconnect sites are formed over a substrate. The bumps are wider than the interconnect sites. The bumps are bonded to the interconnect sites so that the bumps cover a top surface and side surfaces of the interconnect sites. An encapsulant is deposited around the bumps between the semiconductor die and substrate.

A multi-layer pillar and method of fabricating the same is provided. The multi-layer pillar is used as an interconnect between a chip and substrate. The pillar has at least one low strength, high ductility deformation region configured to absorb force imposed during chip assembly and thermal excursions.

The embodiments described above provide enlarged overlapping surface areas of bonding structures between a package and a bonding substrate. By using elongated bonding structures on either the package and/or the bonding substrate and by orienting such bonding structures, the bonding structures are designed to withstand bonding stress caused by thermal cycling to reduce cold joints.

The present disclosure relates to bump structures and a semiconductor device and semiconductor device package having the same. The semiconductor device includes a body, at least one conductive metal pad and at least one metal pillar. The body includes a first surface. The at least one conductive metal pad is disposed on the first surface. Each metal pillar is formed on a corresponding conductive metal pad. Each metal pillar has a concave side wall and a convex side wall opposite the first concave side wall, and the concave side wall and the convex side wall are orthogonal to the corresponding conductive metal pad.

Disclosed are examples of integrated circuit (IC) structures and techniques to fabricate IC structures. Each IC package may include a die (e.g., a flip-chip (FC) die) and one or more die interconnects to electrically couple the die to a substrate. The die interconnect may include a pillar, a wetting barrier on the pillar, and a solder cap on the wetting barrier. The wetting barrier may be wider than the pillar such that during solder reflow, solder wetting of sidewall of the pillar is minimized or prevented all together. The die interconnect may also include a low wetting layer formed on the wetting barrier, which can further mitigate solder wetting problems.

A flip chip interconnect has a tapering interconnect structure, and the area of contact of the interconnect structure with the site on the substrate metallization is less than the area of contact of the interconnect structure with the die pad. A solder mask has an opening over the interconnect site, and the solder mask makes contact with the interconnect structure at the margin of the opening. The flip chip interconnect is provided with an underfill. During the underfill process, the contact or near proximity of the solder mask with the interconnect structure interferes with flow of the underfill material toward the substrate adjacent the site, resulting in formation of a void left unfilled by the underfill, adjacent the contact of the interconnect structure with the site on the substrate metallization. The void can help provide relief from strain induced by changes in temperature of the system.

A flip chip interconnect has a tapering interconnect structure, and the area of contact of the interconnect structure with the site on the substrate metallization is less than the area of contact of the interconnect structure with the die pad. A solder mask has an opening over the interconnect site, and the solder mask makes contact with the interconnect structure at the margin of the opening. The flip chip interconnect is provided with an underfill. During the underfill process, the contact or near proximity of the solder mask with the interconnect structure interferes with flow of the underfill material toward the substrate adjacent the site, resulting in formation of a void left unfilled by the underfill, adjacent the contact of the interconnect structure with the site on the substrate metallization. The void can help provide relief from strain induced by changes in temperature of the system.

A device includes a work piece including a metal bump; and a dielectric layer having a portion directly over the metal bump. The metal bump and a surface of the portion of the dielectric layer form an interface. A metal finish is formed over and contacting the metal bump. The metal finish extends from over the dielectric layer to below the interface.