New materials make microwave components safer for users

DESIGNING and manufacturing high-power microwave components such as transis tors, terminations, and attenuators present challenging materials problems. They are fabricated on substrates which must be temperature and frequency stable, well-matched with other materials used in the construction, have hi gh thermal conductivity (TC), and low parasitic reactance, For many years, beryllium-oxide (BeO) substrates have been used for applications that requi re such characteristics. While the electrical and thermal properties of BeO are attractive, the problem of the material toxicity has caused many users to search for alternatives. According to the Center for Disease Control, t here are chronic and acute reactions which can result from exposure to Be, the base metal in BeO.(1).