The paper presents a review of the causes of phase shift formation in differential communication lines. A zigzag tracing method with an angle of 12° is proposed to compensate for the inhomogeneity of the glass fabric. A method for calculating the formation of skew in the length of conductors at turns with and without rounding is presented.

Keywords: differential pair, differential communication lines, signal phase shift, static skew, dynamic skew, delay, back drilling, non-uniformity effect, fiberglass weave, layout

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