abstract |
A novel substrate is disclosed which can mount either flip-chip solder bonded IC chips or wire bonded chips, or both chips, or a single chip having both solder bonds and wire bonds is disclosed. The substrate has an array of solder pads which will accept solder bonds. Those pads which are to be used for wire bonding have mounted thereon a trimetallic pedestal. Each pedestal has a layer of solder metal bonded to the solder pad, a top layer metal suitable for wire bonding, such as, aluminum or gold, and an intermediate layer of metal, such as nickel, which is impervious to both solder metal and the top layer metal. |