A study of Ni3Sn4 growth dynamics in Ni-Sn TLPS bonding process by differential scanning calorimetry

Transient liquid phase sintering (TLPS) bonding process is a promising packaging process for the new generation semiconductor devices. In this paper, the dynamics of Ni-Sn TLPS bonding is researched. The melting enthalpy and the residual rate of Sn in the simulative and actual bonding process were measured by differential scanning calorimetry. Based on this, the radius of residual Ni particle and thickness of Ni3Sn4 compound were further calculated. The results show that when the initial average radius of Ni particle is 6.5 μm, after holding for 60 min and 240 min at 300 °C, the thickness of Ni3Sn4 is about 4.28 μm and 6.14 μm separately. The thickness Δr of Ni3Sn4 in the simulative bonding process shows a linear relationship as t0.308, i.e. Δr = 1.17t0.308, which is in agreement with that in the actual bonding layer.