Microwave Dielectric Properties of CaTiO₃and MgTiO₃Thin Films

Abstract

The CaTiO3 and MgTiO3 films were prepared by a sol-gel method, and the effect of annealing temperature on the microwave dielectric properties of both films was investigated. It was possible to obtain well-crystallized CaTiO3 and MgTiO3 films with no evidence of secondary phases at 800°C. The dielectric constants (εr) and temperature coefficients of dielectric constant (TCK) of crystalline CaTiO3 and MgTiO3 films were found to increase with an increase in annealing temperature while the dielectric losses (tan δ) tended to decrease in the microwave frequency region. This result was attributed to the enhanced crystallinity and grain size with increasing annealing temperature. εr, tan δ and TCK of CaTiO3 films were about 160, 0.003 ±0.0003 and -1340 ppm/°C at 1–6 GHz. But the MgTiO3 films showed the values of εr ∼16, tan δ∼0.0008 ±0.0001 and TCK ∼+260 ppm/°C, respectively.