Electrical properties of dielectric foil for embedded PCB capacitors

One of the methods of achieving high packaging density of passive elements on the PCB is using the capacitors embedded in multilayer PCB. Test structures consisting of embedded capacitors were fabricated using the FaradFlexA (R) capacitive internal layers. Impedance spectroscopy and equivalent circuit modelling was used to determine their electrical properties such as the capacitance, parasitic resistance and inductance. The use of several stages of accelerated ageing allowed us to test the durability of the structures. The results showed good quality stability of the embedded elements. The spatial distribution of the capacitance of the test structures on the surface of the PCB form was tested. The influence of the process parameters during lamination on the values of embedded capacitors was revealed.