Isothermal Capacitance Transient Spectroscopy of Grain‐Boundary Interfacial States in Beryllium Oxide‐Doped Silicon Carbide Ceramics

Grain boundaries of SiC ceramics doped with 2 wt% BeO were investigated using isothermal capacitance transient spectroscopy (ICTS). ICTS signals were observed above 433 K and the resulting capacitance‐time curves (under bias and zero bias) were ascribed to interfacial states at the grain boundaries. The signals were sharp compared to those of the SrTiO 3 ─Bi 2 O 3 system, suggesting that the structural disorder of grain boundaries in the SiC─BeO system was relatively small. It was determined that the interfacial state was located 0.92 eV above the valence band.