Patent ID: 7723224

Claim:
A method for forming a microelectronic assembly comprising: forming a conductor on a first side of a first substrate having a microelectronic device formed over a second side thereof, the conductor being electrically connected to the microelectronic device and comprising a solderable material; forming a contact structure over the first side of the first substrate, the contact structure being electrically connected to the conductor and comprising a solderable barrier metal, wherein the barrier metal comprises at least one of nickel, chromium-copper, and palladium; forming a non-solderable layer over the contact structure and at least a portion of the first substrate and the conductor, wherein the non-solderable layer is a passivation layer and comprises silicon nitride; removing a portion of the non-solderable layer to expose a portion of the contact structure; forming a solderable layer on the exposed portion of the contact structure; and interconnecting the contact structure and a second substrate with solder, wherein the solder contacts the exposed portion of the contact structure.