Thermomechanical Stresses Simulation in the Structure Redistribution Layers of a Microsystem Design with the Embedded Crystals

Abstract

The paper considers problems of the thermomechanical stresses arising in the redistribution layers during internal installation of crystals into the micro-assembly base with the epoxy monolithizing compound and polyimide microstructure. It describes design and technological limitations of the redistribution layers in the micro assemblies with the embedded crystals. Using the finite element method, thermomechanical stresses in the redistribution layers structure were calculated and analyzed. Based on the calculation results, dependence of thermomechanical stresses in the redistribution layers was determined on the length of conductive tracks, their bend angle and thickness of the conductive and dielectric materials. Simulation also took into account the effect of dielectric and conductive path transition from silicon to the epoxy monolithic compound. Thermomechanical stresses dependence on the distance between parallel tracks and their length was analyzed. The finite element method was used to calculate two design options for constructing the microsystem topology with the integrated FPLD differing in smoothness of the conductive tracks corners, track junctions and contact pads, as well as in thickness of the dielectric and conductive layers. Results of voltage calculations of the two design options for topology of a microsystem with the built-in FPLD chip were comparatively analyzed

This work was performed with the financial support by the RSF grant (project no. 23-29-00964)

Please cite this article in English as:

Kochergin M.D., Solovyov I.A., Vertyanov D.V., et al. Thermomechanical stresses simulation in the structure redistribution layers of a microsystem design with the embedded crystals. Herald of the Bauman Moscow State Technical University, Series Instrument Engineering, 2023, no. 4 (145), pp. 24--42 (in Russ.). DOI: https://doi.org/10.18698/0236-3933-2023-4-24-42

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