Multiphysics Tensorial Network Analysis Applied to PCB Interconnect Fatigue Under Thermal Cycle Aggression.

This paper investigates an original multiphysics KB modeling of the electrothermomechanical (ETM) phenomena in a multi-layer printed circuit board (PCB) under heat cycle aggression. The coupled thermal and intrinsic mechanical interactions with the PCB electrical response are analyzed. The via-interconnect line (IL) junction fatigue caused by the mechanical tensions is explained with tensorial equations. The ETM effects transduced between the PCB components are modeled with equivalent graphs. The multiphysics problem general tensorial relation is formulated. To validate the Kron–Branin model, the numerical application of three-layer PCB proof-of-concept under thermal cycle aggression with 0-to-70 °C variation is introduced. The tensile stresses induced by the thermal effect on the vias and ILs are calculated. The via cracking fatigue model is approximated. The PCB voltage transfer function and input impedance in the function of the thermal aggression are discussed. [ABSTRACT FROM AUTHOR]