Sn/Sn 固相接合強度に対する金属塩生成接合法の適用効果

抄録

  The effect of metal salt generation bonding method on the bond strength of the solid-state bonded interface of tin has been investigated by SEM observation of the interfacial microstructures and fractured surfaces. Metal salt generation was carried out by boiling a tin surface in organic-acid. Solid-state bonding was carried out in a vacuum chamber at bonding temperature T of 393~483 K and bonding pressure P of 7 MPa (bonding time: t = 1800 s). The bond strength increased with an increase in the bonding temperature, independently of the metal salt generation method. Because of the metal salt generation, bonded joints were obtained at a bonding temperature that was 40 K or more than the typical temperature required, and the bond strength was comparable to that of the base metal. When metal salt generation is not applied, the oxide film is destroyed by the improved plastic deformability of the tin. Thus the tensile strength of the joint is increased. On the other hand, when metal salt generation is applied, a high-tensile-strength joint is obtained at a low bonding temperature because metallic tin are exposed at the bond interface as a result of the decomposition of metal salt in the bond interface at a low temperature.