| 摘要 |
PURPOSE:To assure the voidless low thermal resistance bonding process excellent in mechanical strength by a method wherein a melting material as an intermedi ate material is previously provided in the region along the periphery of bonded region such as a semiconductor pellet or a wiring substrate to be heat-melted in the atmosphere at specified pressure. CONSTITUTION:Specimens (an Si chip 11, a solder preform 13 and a heat sink 14) are mounted on a heating base provided in an exhaust system 16 while the atmospheric pressure is reduced down to 1torr. Due to the naturally made minor gaps, the pressure in the inner region 17 of solder preform 13 is immedi ately reduced down to 1torr to heat-melt the solder preform 13 at around 220 deg.C augmenting the liquidity for creating the close contact state or intermetal reac tion state between the metalized layers 12 and 15. The atmospheric pressure is restored to the normal pressure of 760torr with the solder preform 13 heat- melted as it is. Through these procedures, any external pressure is applied on the melted solder preform 13 to reduce the volume of inner region 17 marked ly. Finally, heating process is stopped to bond the solder 13 so that the specified substantial voidless solder bonded structure may be manufactured.
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