This presentation is focusing on aspects on modelling microstructure evolution governed by diffusional phase transformations kinetics, multiple phases and finite strains using the level set method [1]. In the proposed model, the motion of the phase interfaces is governed by the flux directed toward the interface, consistent with diffusional phase transformation kinetics. Moreover, to ensure local equilibrium and maintain a continuous chemical potential across interfaces, chemical composition is prescribed at phase interfaces. An explicit reconstruction of the grain boundaries and triple junction points is performed to accurately solve the diffusion problem in the distinct phases. Once the velocity is determined from the diffusional kinetics, level set functions assigned to the separate phases are advected by the corresponding velocity field, and the new position of the interfaces are conveniently captured by the zero level set contour. The proposed model is applied to study the growth of the intermetallic compound (IMC) $\text{Cu}_6\text{Sn}_5$ in an Sn layer electroplated on Cu. A finite strain formulation is incorporated to account for volume changes resulting from the IMC formation. In this framework, both Cu and Sn are allowed to undergo plastic deformation. Numerical simulations show IMC growth rates in agreement with experimental data. Moreover, the IMC evolves into a scallop-like morphology, which aligns well with experimental observations. The evolution of the biaxial stress in the electroplated Sn layer is in line with experimental measurements obtained by [2].