INORGANIC DIELECTRICS RESEARCH

A comparative study is reported on a boron phosphate silica type composition prepared as a glass, a devitrified body and hot pressed body. The electrical properties versus temperature and frequency indicate that this type composition approaches fused silica. Specimens of lanthanum aluminate were prepared by sintering and hot pressing. A dielectric constant of 25 was obtained for this material. The as-received strength of random samples of 10 types of micromodule wafers is reported. The two approaches to making barium titanate glass are the use of new glass formers and faster frit quenching methods in order to produce a good glass free of devitrified material. A calcium boro-aluminate frit was substituted as the glass former and the flame spraying of 100% BaTiO3 was tried both in an oxygen-hydrogen flame and an oxygenacetylene flame. A study was initiated to attempt to remove the glass forming oxide (B2O3) from the barium titanate-boric oxide frit. The object is to increase the barium titanate content in order to improve the dielectric properties of this type of ferroelectric.