Methods, techniques, and structures relating to die packaging. In one exemplary implementation, a die package interconnect structure includes a semiconductor substrate and a first conducting layer in contact with the semiconductor substrate. The first conducting layer may include a base layer metal. The base layer metal may include Cu. The exemplary implementation may also include a diffusion barrier in contact with the first conducting layer and a wetting layer on top of the diffusion barrier. A bump layer may reside on top of the wetting layer, in which the bump layer may include Sn, and Sn may be electroplated. The diffusion barrier may be electroless and may be adapted to prevent Cu and Sn from diffusing through the diffusion barrier. Furthermore, the diffusion barrier may be further adapted to suppress a whisker-type formation in the bump layer.

An adhesive for a semiconductor, comprising an epoxy resin, a curing agent, and a compound having a group represented by the following formula (1): ##STR00001##
wherein R.sup.1 represents an electron-donating group.

An adhesive for a semiconductor, comprising an epoxy resin, a curing agent, and a compound having a group represented by the following formula (1): ##STR00001##
wherein R.sup.1 represents an electron-donating group.

Embodiments are directed to a method of forming a semiconductor chip package and resulting structures having a mixed under-bump metallization (UBM) size and pitch on a single die. A first set of UBMs having a first total plateable surface area is formed on a first region of a die. A second set of UBMs having an equal total plateable surface area is formed on a second region of the die. A solder bump having a calculated solder height is applied to a plateable surface of each UBM. The solder height is calculated such that a volume of solder in the first region is equal to a volume of solder in the second region.

An integrated circuit device includes a semiconductor substrate; and a pad region over the semiconductor substrate. The integrated circuit device further includes an under-bump-metallurgy (UBM) layer over the pad region. The integrated circuit device further includes a conductive pillar on the UBM layer, wherein the conductive pillar has a sidewall surface and a top surface. The integrated circuit device further includes a protection structure over the sidewall surface of the conductive pillar, wherein sidewalls of the UBM layer are substantially free of the protection structure, and the protection structure is a non-metal material.

Mechanisms for forming a semiconductor device are provided. The semiconductor device includes a contact pad over a substrate. The semiconductor device also includes a passivation layer over the substrate and a first portion of the contact pad, and a second portion of the contact pad is exposed through an opening. The semiconductor device further includes a post-passivation interconnect layer over the passivation layer and coupled to the second portion of the contact pad. In addition, the semiconductor device includes a bump over the post-passivation interconnect layer and outside of the opening. The semiconductor device also includes a diffusion barrier layer physically insulating the bump from the post-passivation interconnect layer while electrically connecting the bump to the post-passivation interconnect layer.

Mechanisms for forming a semiconductor device are provided. The semiconductor device includes a contact pad over a substrate. The semiconductor device also includes a passivation layer over the substrate and a first portion of the contact pad, and a second portion of the contact pad is exposed through an opening. The semiconductor device further includes a post-passivation interconnect layer over the passivation layer and coupled to the second portion of the contact pad. In addition, the semiconductor device includes a bump over the post-passivation interconnect layer and outside of the opening. The semiconductor device also includes a diffusion barrier layer physically insulating the bump from the post-passivation interconnect layer while electrically connecting the bump to the post-passivation interconnect layer.

A semiconductor package structure includes a semiconductor die surface having a narrower pitch region and a wider pitch region adjacent to the narrower pitch region, a plurality of first type conductive pillars in the narrower pitch region, each of the first type conductive pillars having a copper-copper interface, and a plurality of second type conductive pillars in the wider pitch region, each of the second type conductive pillars having a copper-solder interface. A method for manufacturing the semiconductor package structure described herein is also disclosed.

A material for Cu pillars is formed as cylindrical preforms in advance and connecting these cylindrical preforms to electrodes on a semiconductor chip to form Cu pillars. Due to this, it becomes possible to make the height/diameter ratio of the Cu pillars 2.0 or more. Since electroplating is not used, the time required for production of the Cu pillars is short and the productivity can be improved. Further, the height of the Cu pillars can be raised to 200 μm or more, so these are also preferable for moldunderfill. The components can be freely adjusted, so it is possible to easily design the alloy components to obtain highly reliable Cu pillars.

A semiconductor wafer has a plurality of semiconductor die with contact pads for electrical interconnect. An insulating layer is formed over the semiconductor wafer. A bump structure is formed over the contact pads. The bump structure has a buffer layer formed over the insulating layer and contact pad. A portion of the buffer layer is removed to expose the contact pad and an outer portion of the insulating layer. A UBM layer is formed over the buffer layer and contact pad. The UBM layer follows a contour of the buffer layer and contact pad. A ring-shaped conductive pillar is formed over the UBM layer using a patterned photoresist layer filled with electrically conductive material. A conductive barrier layer is formed over the ring-shaped conductive pillar. A bump is formed over the conductive barrier layer. The buffer layer reduces thermal and mechanical stress on the bump and contact pad.