Mechanical and thermo-mechanical stress considerations in applying 3D ICs to a design

This paper provides the physics of failure (PoF) analysis methodology in a three-dimensional integrated circuit (3D IC) integration based on mechanical and thermo-mechanical concepts. The majority of research on the 3D IC package has focused on the Coefficient Thermal Expansion (CTE) mismatch and heat junctions. The primary problems of CTE mismatch and heat dissipation cause failures or fatigues in 3D IC integration, and they become critical reliability issues. However, mechanical stress induced by mechanical loading has a significant effect on the strength of a material, causing, for example, interfacial cracking or the failure of through-silicon-vias. The strategy environment, pressure, and application of mechanical loading all lead to failure concerns. Thus, full 3D IC package modeling needs to be developed to achieve a more reliable 3D IC integration. In this paper, we will discuss the different physics of insight between thermo-mechanical and mechanical loading for 3D IC integration.