Thermomechanical Stress Optimization of Tapered Through-Glass Vias Using Stress-Relief Structures

Through-glass vias (TGVs) are increasingly used in advanced packaging, offering superior performance compared to through-silicon vias (TSVs). However, the thermal expansion mismatch between copper and glass causes significant thermomechanical stresses, which may lead to packaging reliability issues. In this study, we analyzed stress-mitigation strategies for hyperbolic TGVs using finite element modeling. A series of models incorporating various stress-buffer layers and trench isolation structures (annular and shallow trench) were developed to analyze their impact on thermal stress distribution. Simulation results reveal that these strategies effectively reduce interfacial stress concentrations, particularly under elevated temperature conditions. The proposed design modifications offer promising solutions for enhancing the thermomechanical reliability of glass-based packaging platforms.