abstract |
Semiconductor devices containing nickel-titanium (NiTi or TiNi) compounds or alloys and methods for making such devices are described. The devices contain a silicon substrate with an integrated circuit, a contact layer contacting the substrate, a TiNi-containing soldering layer on the contact layer, an oxidation prevention layer on the soldering layer, a solder bump on the soldering layer, and a lead frame or PCB attached to the solder bump. The combination of the Ti and Ni materials in the soldering layer exhibits many features not found in the Ti and Ni materials alone, such as reduced wafer warpage, increased ductility for improved elasticity, decreased consumption of the Ni in the soldering layer, and decreased manufacturing costs. Other embodiments are described. |