Optical sensor modules and methods of fabrication are described. In an embodiment, an optical component is mounted on a module substrate. In an embodiment, a pillar of stacked wireballs adjacent the optical component is used for vertical connection between the module substrate and a top electrode pad of the optical component.

Optical sensor modules and methods of fabrication are described. In an embodiment, an optical component is mounted on a module substrate. In an embodiment, a pillar of stacked wireballs adjacent the optical component is used for vertical connection between the module substrate and a top electrode pad of the optical component.

A method for treating a bare copper wire and a surface-treated copper wire includes applying a solution including a phosphoric acid-based chelating agent to a surface of a bare copper wire, and drying the copper wire having the solution including the phosphoric acid-based chelating agent attached on the surface thereof.

A method for treating a bare copper wire and a surface-treated copper wire includes applying a solution including a phosphoric acid-based chelating agent to a surface of a bare copper wire, and drying the copper wire having the solution including the phosphoric acid-based chelating agent attached on the surface thereof.