Dielectric Properties of Composite PZT Films with Distinct Phase

초록

In various industries, materials that can maintain a high dielectric constant stably are essential. PZT (Lead Zirconate Titanate), known for its high dielectric constant, remains stable up to around 200°C. However, beyond 200°C, it enters a phase transition region, leading to significant fluctuations in dielectric constant, and after the Curie temperature (Tc), where the phase transition ends, the dielectric constant drops sharply. This makes it difficult to use PZT in the temperature range where it has the highest dielectric constant. To address this issue, our study introduces a process that smooths the phase transition region. We selected PZT 5:5, which has the highest dielectric constant in the MPB (Morphotropic Phase Boundary) region, and PZT 2:8 and 8:2, each with different Tc, and mixed them. Using aerosol deposition, we created dielectric films. Aerosol deposition allows film formation at room temperature without the need for sintering, enabling the preservation of different phase transition temperatures for each composition. Introducing these compositions into different phase coexistence regions smooths the phase transition, improving the narrow Tc range. This expands PZT's application potential beyond room temperature, enabling its use across a broader temperature range with high dielectric constant, laying the groundwork for industrial applications requiring stable, high dielectric properties.