The solder system includes two copper contact pads connected by a body of solder and the solder is an alloy including tin, silver, and at least one metal from the transition groups IIIA, IVA, VA, VIA, VIIA, and VIIIA of the Periodic...http://www.google.com/patents/US7626274?utm_source=gb-gplus-sharePatent US7626274 - Semiconductor device with an improved solder jointAdvanced Patent SearchPublicati