PB SOLDER ALLOY MATERIAL FOR ASSEMBLING SEMICONDUCTOR DEVICE HAVING EXCELLENT HIGH-TEMPERATURE STRENGTH

摘要

PURPOSE:To form soldered parts which exhibit excellent hightemp. strength and do not fracture even in practicable use when the solder material is used for assembly of highly integrated semiconductor devices which entails high heat generation by composing the solder material of a Pb alloy contg. a specific range of Pb by weight% and consisting of the balance Pb and inevitable impurities. CONSTITUTION:The reason for specifying the content of the Pb which is an alloy component in the Pb alloy constituting the Pb alloy solder material to 3 to 12% lies in that the desired high temp. cannot be assured if the content thereof is below 3% and that the m. p. is too high and soldering is difficult if the content thereof exceeds 12%. The content thereof is thus specified to 3 to 12%. Since such Pb alloy solder material has the excellent high-temp. strength, the soldered parts do not fracture at the time of practicable use when such solder material is used in assembly of the highly integrated semiconductor devices which particularly entails high heat generation. The high reliability is thus assured over a long period of time.