Next: 3.3.1 Effect of Vacancy Transport Up: 3. Modeling Electromigration Using TCAD Previous: 3.2.1 Vacancy Sources and Sinks
In Section 3.2, it is stated that the redistribution of vacancy concentration in the interconnect line is mainly caused by the contributions of two mechanisms: vacancy accumulation/depletion, due to the vacancy-atom exchange process, and the generation/annihilation of vacancies, due to the source/sink process. As previously discussed in Section 2.5, the vacancy flow as well as the creation and annihilation of vacancies inside an interconnect lead to the development of volumetric strain in the metal line. Therefore, the strain induced by electromigration at any point in an interconnect occurs either by vacancy transport or by vacancy generation/annihilation. Metals respond to strains by deforming and/or by the build-up of stress.