THE EFFECT OF ELASTIC MODULUS RATIO ON INCLUSION EVOLUTION BY INTERFACE MIGRATION

Defects such as inclusions are inevitably presented in the wires of integrated circuit. Under the effect of various internal mechanisms and external environment, the morphology evolution of the inclusions will affect the performance of the interconnects. Based on the weak statement of microstructure evolution for the interface migration, the governing equations of stress-induced solid-solid interface migration are derived, and the effects of the Young's modulus ratio of the inclusion and the matrix on the morphology evolution of inclusion are numerically simulated. The results show that: there are two kinds of bifurcation trends in the morphology evolution of the inclusions, and exist the critical stress \widetilde \sigma _\rmc, the critical aspect ratio \beta _\rmc and the critical line width \widetilde h_\rmc. When \widetilde \sigma > \widetilde \sigma _\rmc, \beta > \beta _\rmc or \widetilde h < \widetilde h_\rmc , the inclusion grows. Otherwise, the inclusion will shrink. As the modulus ratio increases, the critical stress or the critical aspect ratio increases, and the critical linewidth decreases. Also, when the Young's modulus ratio of the inclusion to the matrix \alpha > 0.6, the effect of the modulus ratio on the critical stress and the critical aspect ratio can be ignored.