Explicit Analytical Model of Stretchable Interconnects for Flexible Electronics System

A printed circuit board (PCB) is one of the strong backbones to execute electronic system designs. Due to fast and reliable communication requirements between integrated circuit and other peripheral components over the PCB, there is a quest for the development of board-level designs and layouts. The advancement in technology has led to inventions from conventional rigid to flexible PCBs or flexible electronics (FE). The conformability of FE circuitry majorly depends upon the stretchable interconnects. An interconnect is the medium through which a signal is transmitted. The characteristic of stretchable interconnects is determined through their electrical and mechanical properties. The analytical model and parasitic extraction of the interconnect for rigid PCB structures have been widely explored earlier. However, the analytical formulation of the stretchable interconnect still remains a challenge and meagerly explored till date. Consequently, in this work, an explicit analytical model for the parasitic extraction of stretchable interconnects, viz., resistance ($R$), inductance ($L$), and capacitance ($C$), under stretching and bending effects has been novelly proposed. Five different interconnect materials have been considered for the analysis. The analytical model results have been validated with the ANSYS EDA tool. It is investigated that the proposed analytical model results are in very close agreement with the ANSYS results for all the considered cases.