| 초록 |
With development of electrical industry, demand for a ceramic based capacitor with high energy storage density has been increased gradually. In the use of electrical devices, heat generation is inevitable and most of ceramic dielectrics have a low thermal stability. Efficiency considered as key factor of energy storage density is sensitive to high temperature. Therefore, finding ceramic materials of the good thermal stability becomes more significant. Today, lead zirconate titanate(PZT) has been widely used in electrical devices because of their high polarity and dielectric constant. However a lead-free materials substituted for PZT are being requested increasingly due to their environmental problems. In this study, we have designed lead-free partially calcined compound and calcined compound of 0.6Bi0.5Na0.5TiO3(BNT)-0.4Sr0.7Bi0.2TiO3(SBT). Compared to dielectric properties and thermal stability, both compound of 0.6BNT-0.4SBT were fabricated to thick film by aerosol deposition method(AD). AD method, based on particle’s physical collision can fabricate dense film on substrate at room temperature without additional sintering process which is usually required to ceramic materials. Through the novel AD method, artificially engineered relaxor ferroelectric thick film with nano-grain can be fabricated at room temperature, exhibiting high energy storage performance. This study suggests that partially calcined 0.6BNT-0.4SBT thick film fabricated by AD method shows great dielectric properties, thermal stability than calcined compound. |
