Low-temperature synthesis and microwave dielectric properties of Mg4Nb2O9 ceramics synthesized by a precipitation method

The Mg4Nb2O9 (MN) ceramic was prepared by a precipitation method in order to develop a low-temperature sintering substrate for use in multilayer microwave integrated circuit (MMIC) applications. The MN ceramic was produced at a temperature of 700degreesC; the dielectric constant (epsilon(r)) and the quality factor (Q(.)f) of MN sintered at 950degreesC for 2 h in air were 8.5 and 5500 GHz, respectively. A chemical reaction between MN and Ag, which is one of the electrode materials for MMIC applications, was not seen in the XRPD pattern when the MN and Ag powders were heat-treated at 950degreesC for 2 h in air. (C) 2003 Elsevier B.V. All rights reserved.