| 摘要 |
PURPOSE:To provide a preform soft brazing material having structure of either solid solution having no precipitates or in which precipitates are uniformly distributed by rapidly cooling at a cooling speed of 10<3> deg.C/sec or more a molten soft brazing alloy from a temperature higher than its liquid phase line. CONSTITUTION:A soft brazing alloy such as Sn based alloy contg. at least one of Sb: 5-20wt%, Au: 1-20wt%, and Ag: 3.5-20wt% is rapidly cooled from a temperature higher than its liquid phase line, at a cooling rate of 10<3> deg.C/sec or higher, by means of roller quenching method in which the molten alloy is injected from nozzle by inert gas pressure between high-speed rotating rollers. Thus, the metal is rolled at the same time and formed into thin formed body of soft brazing material plate. Using this soft brazing material to bond a semiconductor element and a heat sink greatly improves the uniformity in bonding property and thermal fatigue caused by stress due to the strain between the element and heat sink. |
