图5. Cu/Sn-37Pb/Cu焊点液-固电迁移过程Pb原子扩散通量及微观组织演变示意图

Fig.5. Schematics of the Pb atomic fluxes and the microstructural evolution in Cu/Sn-37Pb/Cu interconnects during L-S EM (J_{\mathrm{c}\mathrm{h}\mathrm{e}\mathrm{m}}^{\mathrm{P}\mathrm{b}} and J_{\mathrm{e}\mathrm{m}}^{\mathrm{P}\mathrm{b}} are the Pb atomic fluxes induced by chemical potential gradient and EM, respectively)(a) heating stage (b) dwelling stage (c) cooling stage