Frequency Dependence Examination of PCB Material FR4 Relative Permittivity

At the microwave frequencies high requirements are put on the materials for construction of final devices. A number of dielectric substrates are available for microstrip technologies but the prices of these materials are directly proportional to their good dielectric features. Application of low cost materials can cause serious inaccuracies if the design of device assumed better quality of materials. This paper deals with examination of relative permittivity (dielectric constant) of widely used FR4 material for construction of PCB (Printed Circuit Boards). The examination is based on calculations and measurements of functional sample which was manufactured for this purpose.