Single Level Integrated Module (SLIM) is a next-generationelectronic packaging module that has the potential for high performance,low cost and small size. The proposed SLIM structure is a multi-layeredstructure with embedded passive layers in addition to signal, ground andpower planes. At fabrication, assembly and different field conditions,significant interfacial stresses could develop due to the mismatch ofthe Coefficient of Thermal Expansion (CTE) among its different materialsystems. One of the most common failure modes in such a multi-layeredstructure is interfacial delamination. The objective of this research isto examine the possibilities of interfacial delamination in thismulti-layered structure under thermal loading. A sophisticatedanalytical model has been developed in this work to determine energyrelease rate and stress intensity factor for delamination propagation.The model takes into consideration the temperature-dependent materialproperties as well as orthotropic material properties. Althoughdelamination between two adjacent layers is studied, the model takesinto consideration the effect of all dielectric, metallization, andsubstrate layers. Assuming that an initial delamination exists betweenthe base layer and the metallization Copper layer, this work studies thepropagation of delamination. In the analytical model, the base layer ismodeled as an orthotropic thermoelastic material. Copper and the polymerdielectric material are modeled as isotropic elastic material. For theCopper/base layer interface, the variation of bimaterial constant(ε) with temperature is obtained through the analytical model. Theeffect of some key parameters, such as the base layer material, theinterlayer dielectric material, the metallization layer material, thebase layer thickness, and the temperature range, etc. on energy releaserate and fracture mode ratio is presented. Design recommendations forimproved thermomechanical reliability are proposed
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