Flux formulations and solder attachment during the fabrication of electronic device assemblies are described. One flux formation includes a flux component and a metal particle component, the metal particle component being present in an amount of from 5 to 35 volume percent of the flux formulation. In one feature of certain embodiments, the metal particle component includes solder particles. Other embodiments are described and claimed.

Flux formulations and solder attachment during the fabrication of electronic device assemblies are described. One flux formation includes a flux component and a metal particle component, the metal particle component being present in an amount of from 5 to 35 volume percent of the flux formulation. In one feature of certain embodiments, the metal particle component includes solder particles. Other embodiments are described and claimed.

The present disclosure provides a semiconductor package, which includes a substrate, a passivation layer, a post-passivation interconnect (PPI) having a top surface; and a conductive structure. The top surface of the PPI includes a first region receiving the conductive structure, and a second region surrounding the first region. The second region includes metal derivative transformed from materials made of the first region. The present disclosure provide a method of manufacturing a semiconductor package, including forming a first flux layer covering a portion of a top surface of a PPI; transforming a portion of the top surface of the PPI uncovered by the first flux layer into a metal derivative layer; removing the first flux layer; forming a second flux layer on the first region of the PPI; dropping a solder ball on the flux layer; and forming electrical connection between the solder ball and the PPI.

A method of manufacturing a semiconductor package according to the present inventive concepts comprises preparing a printed circuit board (PCB) including a protected layer, exposing a portion of the protected layer from the insulating layer, forming a solder ball land by processing the exposed surface of the protected layer, forming a solder ball on the solder ball land, and mounting a semiconductor chip on the solder ball formed on the PCB. The solder balls include copper of about 0.01 wt % to about 0.5 wt %.

An integrated circuit structure includes a substrate, a metal pad over the substrate, a passivation layer having a portion over the metal pad, and a polymer layer over the passivation layer. A Post-Passivation Interconnect (PPI) has a portion over the polymer layer, wherein the PPI is electrically coupled to the metal pad. The integrated circuit structure further includes a first solder region over and electrically coupled to a portion of the PPI, a second solder region neighboring the first solder region, a first coating material on a surface of the first solder region, and a second coating material on a surface of the second solder region. The first coating material and the second coating material encircle the first solder region and the second solder region, respectively. The first coating material is spaced apart from the second coating material.

Embodiments of the present disclosure include interconnect structures and methods of forming interconnect structures. An embodiment is an interconnect structure including a post-passivation interconnect (PPI) over a first substrate and a conductive connector on the PPI. The interconnect structure further includes a molding compound on a top surface of the PPI and surrounding a portion of the conductive connector, a top surface of the molding compound adjoining the conductive connector at an angle from about 10 degrees to about 60 degrees relative to a plane parallel with a major surface of the first substrate, the conductive connector having a first width at the adjoining top surface of the molding compound, and a second substrate over the conductive connector, the second substrate being mounted to the conductive connector.

A method of forming bond pads includes providing a substrate including an integrated circuit (IC) device formed thereon having an oxidizable uppermost metal interconnect layer which provides a plurality of bond pads that are coupled to circuit nodes on the IC device. The plurality of bond pads includes a metal bond pad area. A cobalt including connection layer is deposited directly on the metal bond pad area. The cobalt including connection layer is patterned to provide a cobalt bond pad surface for the plurality of bond pads, and a solder material is formed on the cobalt bond pad surface.

A method of forming bond pads includes providing a substrate including an integrated circuit (IC) device formed thereon having an oxidizable uppermost metal interconnect layer which provides a plurality of bond pads that are coupled to circuit nodes on the IC device. The plurality of bond pads includes a metal bond pad area. A cobalt including connection layer is deposited directly on the metal bond pad area. The cobalt including connection layer is patterned to provide a cobalt bond pad surface for the plurality of bond pads, and a solder material is formed on the cobalt bond pad surface.

A one-step water soluble (WS) flux process may reduce residue staining and increase yields for bond grid array (BGA) packages. In one example, the WS flux may use increased amounts of bonding polymer (BP) and reduced amounts of amine to increase viscosity. The increased viscosity may eliminate using a second no-clean flux and enable a single WS flux to both clean the associated substrate and provide stable solder ball support during reflow.

Packaging devices and methods of manufacture thereof for semiconductor devices are disclosed. In some embodiments, a packaging device includes a contact pad disposed over a substrate, and a passivation layer disposed over the substrate and a first portion of the contact pad. A post passivation interconnect (PPI) line is disposed over the passivation layer and is coupled to a second portion of the contact pad. A PPI pad is disposed over the passivation layer. A transition element is disposed over the passivation layer and is coupled between the PPI line and the PPI pad. The transition element comprises a first side and a second side coupled to the first side. The first side and the second side of the transition element are non-tangential to the PPI pad.