Multilayer edge commutation in 3D integration technologies can simplify the design of microassemblies and reduce the length of edge electrical connections. However, this commutation is vulnerable to thermomechanical stresses and requires preliminary analysis of the product design. This paper shows the results of modeling various variants of multilayer edge commutation for 3D microassemblies, differing both in the dielectric material used at the edge redistribution layer and in the material for sealing the microassembly volume. It has been established that the lowest values ​​of thermomechanical stresses in commutation are characteristic of materials whose temperature coefficient of linear expansion is as close as possible to this parameter of conductors. At the same time, the use of composite dielectrics in redistribution layers leads to a more significant decrease in stresses than the use of more thermally stable unfilled polymers.

Keywords: 3D integration, packaging, thermomechanical stresses, polyimide, redistribution layer

This work investigated the influence of the type of vertical switching on the level of thermomechanical stresses and temperature deformation in a three-dimensional microassembly. Three microassembly models with the most common types of vertical connections were considered: solder balls in the package holes, metallized holes in the package, and end-switching tracks. For each of the three models, the effect of the sealing compound parameters on the thermomechanical load was additionally investigated.

Keywords: microassembly, packaging, electronic component base, three-dimensional integration, vertical switching, thermomechanical stress, thermomechanical deformation, thermal coefficient of linear expansion, thermomechanical modeling