The multicomponent nature of power electronic devices can be an issue for their reliability due to the high currents and temperatures reached during operation. Proper design of each component and the system as a whole is mandatory to ensure a long lifetime and small failure rates. In this work, we systematically investigate the influence of manufacturing on the behavior of press-fit rectifier Si diodes by introducing changes in the manufacturing process. Concretely, we focused on the solder geometry and the epoxy component. Thermography measurements and computational modeling show that optimization of the solder thickness and its uniformity allows the diode to bear higher currents and temperatures close to 250 °C in the hottest parts of the device (located in the epoxy zones) without failure. In addition, choosing an adequate epoxy with a limited expansion rate over a wide temperature range helps to reduce stress and strain effects, preventing the breakdown of the diodes even at continuous currents up to 40 A. © 2023

This work was supported by the Spanish Ministry for Science and Innovation (MCIN) under the projects PID2021-124585NB-C33 and PID2020-114192RB-C41. S.R.-S. acknowledges the financial support from the FARDIO project to SEG Automotive Germany GmbH. M.P.O. acknowledges financial support from the Spanish Ministry of Universities, through the FPU program (FPU20/03166) . A.S. acknowledges the financial support from MCIN for a Ramon y Cajal contract (No. RYC2021-031236-I) , which is funded by the Recovery, Transformation and Resilience plan.

Peer reviewed