Thermal Shift in Electrical Behavior of Substrate Materials with Improved Flame Resistance

A halogen-free class of materials for PCB substrate was considered here, with good properties of electrical safety of flammability. The electrical properties of this class of materials were analyzed in this paper by calculating the HF values for the effective permittivity of these materials and illustrating its evolution with frequency and temperature. We have used a CAD technique which was developed by conceiving an algorithm based on physical considerations for effective permittivity calculation, with help of a high level computing program, specialized in HF and microwave range. The resonant electrical behavior of the considered materials was illustrated and our new contribution was to compute the thermal shift of these resonances for each material. Results interpretations and comments are also available, to explain the thermal shift link with materials components structure. This study continues our work in the field of new PCB materials characterization. Similar analyzes were performed by us for other halogen-free PCB material classes and our intention is to develop our data base for concluding finally on materials properties and their HF and temperature behavior for materials exploitation optimization and completing the electric compatibility rules.