Measurements of loss tangent and relative permittivity of LTCC ceramics at varying temperatures and frequencies

Precise knowledge of microwave properties of LTCC materials is crucial for efficient design of microwave systems, especially for design of communication filters. In this paper relative permittivity εr and loss tangent tanδ of a variety of LTCC ceramics manufactured by Heraeus Circuit Materials Division are presented for frequencies of 3.3 and 5.5 GHz at room temperature and also for temperatures varying from −33 °C to 22 °C at a frequency of 3.3 GHz. The measurement system for microwave characterisation of LTCC materials was based on the split post dielectric resonator and the Transmission Mode Q-factor techniques with random uncertainty in εr and in tanδ better than 0.5 and 2.6% respectively.