Dielectric breakdown behavior of oxynitride glass

Abstract

This study presents the first direct measurement of the dielectric breakdown strength (DBS) of oxynitride glass, providing new insights into its electrical insulation properties. Oxynitride glass was prepared using a blend of Si₃N₄, SiO₂, Y₂O₃, and MgO powders and formed into thin glass substrates of varying thicknesses. The DBS measurement was conducted by using circular column shape and McKewon electrodes. DBS measurements revealed that the oxynitride glass exhibited consistently slightly lower DBS values than Si₃N₄ sintered bodies across all tested thicknesses. This finding suggests that DB in Si₃N₄ predominantly occurs within the grain boundary glass phase. These results, aligning with previous studies on the dielectric breakdown mechanisms of silicon nitride ceramics, confirmed the critical role of the grain boundary glass phase in determining their electrical insulation performance.