Patent ID: 6574859
Filing Date: 2003-06-10
Classification: H01L,H05K,Y02P,Y10T

Abstract:
A method for forming a connection between substrates comprising:a) bonding a connector to an electrical conductive portion of a first substrate, with a first solder bond comprising a combination of a Pbâ€”Sn eutectic and a Pbâ€”Sn alloy having a combined first melting point, and an alloying additive powder having a melting point higher than said first melting point and making a joint composition paste with a liquidus higher than said first melting point, by heating said first solder to a temperature higher than said first melting point; and b) bonding an opposite end of said connector to an electrical conductive portion of a second substrate with a second solder bond comprising a eutectic having a second melting point, wherein said second melting point is lower than said first solder bond first melting point.