Patent ID: 6956292
Filing Date: 2005-10-18
Classification: H01L

Abstract:
1. A semiconductor structure, comprising: at least one contact pad provided on the surface of a substrate; a layer of passivation material deposited over the surface of said substrate, said layer of passivation material having at least one opening that aligns with said at least one contact pad; at least one layer of seed material deposited over said layer of passivation material, the seed layer contacting a surface of the contact pad; at least one layer of Under Bump Metal (URM) deposited over the surface of said layer of seed material; at least one layer of solder material having a solder height provided over the surface of said at least one layer of UBM; a layer of polymer material deposited over the layer of passivation material to a polymer thickness, said polymer thickness being less than said solder height, said polymer contacting said layer of solder material over a substantial portion of the thickness of the polymer layer; the polymer layer further having an opening aligned with the contact pad; wherein the solder layer is disposed within the opening in the polymer layer, the solder layer height being greater than the polymer layer thickness; the solder layer comprising a column portion having a substantially cylindrical shape with a first diameter and a bump portion having a second diameter, the bump portion further having a substantially spherical shape; and wherein the column portion is disposed within the opening and has a height substantially equal to the polymer layer thickness, the bump portion extends above a top surface of the polymer layer thickness, and the first diameter is substantially smaller than the second diameter.