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 microelectronic device has a bump bond structure including an electrically conductive pillar with an expanded head, and solder on the expanded head. The electrically conductive pillar includes a column extending from an I/O pad to the expanded head. The expanded head extends laterally past the column on at least one side of the electrically conductive pillar. In one aspect, the expanded head may have a rounded side profile with a radius approximately equal to a thickness of the expanded head, and a flat top surface. In another aspect, the expanded head may extend past the column by different lateral distances in different lateral directions. In a further aspect, the expanded head may have two connection areas for making electrical connections to two separate nodes. Methods for forming the microelectronic device are disclosed.

A microelectronic device has a bump bond structure including an electrically conductive pillar with an expanded head, and solder on the expanded head. The electrically conductive pillar includes a column extending from an I/O pad to the expanded head. The expanded head extends laterally past the column on at least one side of the electrically conductive pillar. In one aspect, the expanded head may have a rounded side profile with a radius approximately equal to a thickness of the expanded head, and a flat top surface. In another aspect, the expanded head may extend past the column by different lateral distances in different lateral directions. In a further aspect, the expanded head may have two connection areas for making electrical connections to two separate nodes. Methods for forming the microelectronic device are disclosed.

A microelectronic device includes a reflow structure. The reflow structure has a copper-containing member and a solder member, and a barrier layer between them. The barrier layer has metal grains, with a diffusion barrier filler between the metal grains. The metal grains include at least a first metal and a second metal, each selected from nickel, cobalt, lanthanum, and cerium, with each having a concentration in the metal grains of at least 10 weight percent. The diffusion barrier filler includes at least a third metal, selected from tungsten and molybdenum. A combined concentration of tungsten and molybdenum in the diffusion barrier filler is higher than in the metal grains to provide a desired resistance to diffusion of copper. The barrier layer includes 2 weight percent to 15 weight percent of the combined concentration of tungsten, and molybdenum. A bump bond structure and a lead frame package are disclosed.

A semiconductor chip, a display device or an electronic device includes a substrate, one or more conductive pads disposed on the substrate, and one or more bumps electrically connected to the one or more conductive pads, in which the one or more bumps includes a metal core, a polymer layer disposed over a surface of the metal core, and a conductive coating layer disposed over a surface of the polymer layer and electrically connected to the one or more conductive pads.

A semiconductor chip, a display device or an electronic device includes a substrate, one or more conductive pads disposed on the substrate, and one or more bumps electrically connected to the one or more conductive pads, in which the one or more bumps includes a metal core, a polymer layer disposed over a surface of the metal core, and a conductive coating layer disposed over a surface of the polymer layer and electrically connected to the one or more conductive pads.

A semiconductor device includes a semiconductor chip having a pad which is exposed through a passivation layer, a bump pillar formed over the passivation layer adjacent to the pad, but not overlapping with the pad. The semiconductor chip also has a solder layer including a solder bump portion which is formed over the bump pillar and a solder fillet portion which is formed at one side of the bump pillar facing the pad to cover the pad and electrically couples the bump pillar and the pad.

A semiconductor device includes a semiconductor chip having a pad which is exposed through a passivation layer, a bump pillar formed over the passivation layer adjacent to the pad, but not overlapping with the pad. The semiconductor chip also has a solder layer including a solder bump portion which is formed over the bump pillar and a solder fillet portion which is formed at one side of the bump pillar facing the pad to cover the pad and electrically couples the bump pillar and the pad.

Embodiments of the present disclosure are directed towards techniques and configurations of interconnect structures having a polymer core in integrated circuit (IC) package assemblies. In one embodiment, an apparatus includes a first die having a plurality of transistor devices disposed on an active side of the first die and a plurality of interconnect structures electrically coupled with the first die, wherein individual interconnect structures of the plurality of interconnect structures have a polymer core, and an electrically conductive material disposed on the polymer core, the electrically conductive material being configured to route electrical signals between the transistor devices of the first die and a second die. Other embodiments may be described and/or claimed.

Embodiments of the present disclosure are directed towards techniques and configurations of interconnect structures having a polymer core in integrated circuit (IC) package assemblies. In one embodiment, an apparatus includes a first die having a plurality of transistor devices disposed on an active side of the first die and a plurality of interconnect structures electrically coupled with the first die, wherein individual interconnect structures of the plurality of interconnect structures have a polymer core, and an electrically conductive material disposed on the polymer core, the electrically conductive material being configured to route electrical signals between the transistor devices of the first die and a second die. Other embodiments may be described and/or claimed.