In embodiments, a semiconductor package may include a first die and a second die. The package may additionally include a serializer/deserializer (SerDes) die coupled with the first and the second dies. The SerDes die may be configured to serialize signals transmitted from the first die to the second die, and deserialize signals received from the second die. Other embodiments may be described and/or claimed.

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. The die interconnect may also include a low wetting layer formed on the wetting barrier.

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. The die interconnect may also include a low wetting layer formed on the wetting barrier.

A semiconductor package is provided. The semiconductor package includes: a first stack including a first semiconductor substrate; a through via that penetrates the first semiconductor substrate in a first direction; a second stack that includes a second face facing a first face of the first stack, on the first stack; a first pad that is in contact with the through via, on the first face of the first stack; a second pad including a concave inner side face that defines an insertion recess, the second pad located on the second face of the second stack; and a bump that connects the first pad and the second pad, wherein the bump includes a first upper bump on the first pad, and a first lower bump between the first upper bump and the first pad.

Provided is a semiconductor package including a first bump pad on a first substrate, a second bump pad on a second substrate, a core material for reverse reflow between the first bump pad and the second bump pad, and a solder member forming a solder layer on the core material for reverse reflow. The solder member is in contact with the first bump pad and the second bump pad. Each of a first diameter of the first bump pad and a second diameter of the second bump pad is at least about 1.1 times greater than a third diameter of the core material for reverse reflow. The core material for reverse reflow includes a core, a first metal layer directly coated on the core, and a second metal layer directly coated on the first metal layer.

Provided is a semiconductor package including a first bump pad on a first substrate, a second bump pad on a second substrate, a core material for reverse reflow between the first bump pad and the second bump pad, and a solder member forming a solder layer on the core material for reverse reflow. The solder member is in contact with the first bump pad and the second bump pad. Each of a first diameter of the first bump pad and a second diameter of the second bump pad is at least about 1.1 times greater than a third diameter of the core material for reverse reflow. The core material for reverse reflow includes a core, a first metal layer directly coated on the core, and a second metal layer directly coated on the first metal layer.

An integrated circuit includes a substrate, a pad electrode disposed on the substrate, and a passivation layer disposed on the pad electrode and including an organic insulating material. The integrated circuit further includes a bump electrode disposed on the passivation layer and connected to the pad electrode through a contact hole. The passivation layer includes an insulating portion having a first thickness and covering an adjacent edge region of the pad electrode and the substrate, and a bump portion having a second thickness, that is greater than the first thickness, and covering a center portion of the pad electrode.

An integrated circuit includes a substrate, a pad electrode disposed on the substrate, and a passivation layer disposed on the pad electrode and including an organic insulating material. The integrated circuit further includes a bump electrode disposed on the passivation layer and connected to the pad electrode through a contact hole. The passivation layer includes an insulating portion having a first thickness and covering an adjacent edge region of the pad electrode and the substrate, and a bump portion having a second thickness, that is greater than the first thickness, and covering a center portion of the pad electrode.

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.

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.