Semiconductor devices and methods of manufacture thereof are disclosed. In some embodiments, a method includes forming a contact pad over a semiconductor device. A passivation material is formed over the contact pad. The passivation material has a thickness and is a type of material such that an electrical connection may be made to the contact pad through the passivation material.

A semiconductor structure includes a first contact pad over a passivation layer, wherein the first contact pad is in a circuit region. The semiconductor structure further includes a plurality of second contact pads over the passivation layer, wherein each second contact pad of the plurality of second contact pads is in a non-circuit region. The semiconductor structure further includes a first buffer layer over the first contact pad and over a first second contact pad of the plurality of second contact pads. The semiconductor structure further includes a second buffer layer over the first buffer layer, the first contact pad, the first second contact pad and a portion of a second second contact pad of the plurality of second contact pads, wherein the second buffer layer exposes a portion of the second second contact pad of the plurality of second contact pads.

Semiconductor devices and methods of manufacture thereof are disclosed. In some embodiments, a method includes forming a contact pad over a semiconductor device. A passivation material is formed over the contact pad. The passivation material has a thickness and is a type of material such that an electrical connection may be made to the contact pad through the passivation material.

A method of forming an electrical contact is provided. The method may include depositing, by atomic layer deposition, a passivation layer over at least a region of a metal surface, wherein the passivation layer may include aluminum oxide, and electrically contacting the region of the metal surface with a metal contact structure, wherein the metal contact structure may include copper.

A method of fabricating a semiconductor device includes forming a first contact pad and a second contact pad over a first passivation layer, depositing a first buffer layer over the first contact pad and the second contact pad, and depositing a second buffer layer over the first buffer layer and the second contact pad. The first contact pad is in a circuit region and the second contact pad is in a non-circuit region. An edge of the second contact pad is exposed and a periphery of the first contact pad and an edge of the second contact pad are covered by the first buffer layer.

A semiconductor device includes: a semiconductor substrate having a first main surface; an aluminum electrode having a first surface facing the first main surface and a second surface opposite to the first surface, the aluminum electrode being disposed on the semiconductor substrate; a passivation film that covers a peripheral edge of the second surface and that is provided with an opening from which a portion of the second surface is exposed; a copper film disposed on the second surface exposed from the opening so as to be separated from the passivation film; and a metal film disposed on the second surface exposed from between the passivation film and the copper film. The metal film is constituted of at least one selected from a group consisting of a nickel film, a tantalum film, a tantalum nitride film, a tungsten film, a titanium film, and a titanium nitride film.

A method of fabricating a semiconductor device includes forming a first contact pad and a second contact pad over a first passivation layer, depositing a first buffer layer over the first contact pad and the second contact pad, and depositing a second buffer layer over the first buffer layer and the second contact pad. The first contact pad is in a circuit region and the second contact pad is in a non-circuit region. An edge of the second contact pad is exposed and a periphery of the first contact pad and an edge of the second contact pad are covered by the first buffer layer.

Wafers and methods of forming solder balls include etching a hole in a final redistribution layer over a terminal contact pad on a wafer to expose the terminal contact pad. Solder is injected into the hole using an injection nozzle that is in direct contact with the final redistribution layer. The final redistribution layer is etched back. The injected solder is reflowed to form a solder ball.

A semiconductor element having an interconnect bonding layer with a contact pad and a plasma damage-free low-k dielectric material is disclosed. The contact pad connects an underlying conductive feature through an intervening via. A thin dielectric layer is disposed on and covering the entire sidewalls of the contact pad, the intervening via and the underlying conductive feature, and making an approximately right angle turn to extend along an interface between the low-k dielectric material and a first dielectric layer that at least partially bury the underlying contact feature.

Wafers include multiple bulk redistribution layers. A contact pad is formed on a surface of one of the bulk redistribution layers. A final redistribution layer is formed on the surface and in contact with the contact pad. Solder is formed on the contact pad. The solder includes a pedestal portion formed to a same height as the final redistribution layer and a ball portion above the pedestal portion.