Dielectric properties' homogeneity of various substrates in GHz area

This paper is focused on investigation of dielectric properties' homogeneity of various substrates. Dielectric constant and loss tangent of polymeric flexible substrates (Polyimide DuPont Kapton HN, PET Mylar A, PEN Teonex Q51), insulation paper (Nomex 410), Low Temperature Co - fired Ceramic (LTCC) substrate (DuPont GreenTape 951) and Printed Circuit Board (PCB) substrate (RT/duroid 5880) were measured. Measurements were done by combination of Vector Network Analyzer (VNA) and split cylinder resonator. This measuring method provides dielectric properties at frequency around 10 GHz, the exact value of frequency may vary depends on specific material. Samples with dimensions 12× 12 cm were divided into 9 overlapping areas (6× 6 cm). Dielectric properties of all substrates were measured in each of 9 areas and results were statistically processed and depicted by SigmaPlot software.