솔 - 젤법을 이용한 Bismuth Layered Structure를 가진 강유진성 박막의 제조 및 특성평가에 관한 연구 (II. MOD법으로 제조한 강유전성 $Sr_{0.7}/B_{2.3}(Ta_{1-x}Nb_x)_2O_9$ 박막의 유전특성) = The Preparation and Characterization of Bismuth Layered Ferroelectric Thin Films by Sol-Gel Process (II. Dielectric Properties of Ferroelectric $Sr_{0.7}/B_{2.3}(Ta_{1-x}Nb_x)_2O_9$ Thin Films Prepared by MOD Process)

다국어 초록 (Multilingual Abstract)

Ferroelectric $Sr_{0.7}/B_{2.3}(Ta_{1-x}Nb_x)_2O_9$(x=0, 0.1, 0.2, 0.3) thin films were deposited on $Pt/SiO_2/Si$ substrate by MOD(Metalorganic Decomposition) process. Metal carboxylate and metal alkoxide were used as precursors, and 2-methoxyethanol, xylene as solvents. After spin coating, thin films were pre-annealed at $400^{\circ}C$, followed by RTA(Rapid Thermal Annealing) and final annealing at $800^{\circ}C$ in oxygen atmosphere. These procedures were repeated three times to obtain thin films with the thickness of $2000{\AA}$. To enhance the nucleation and growth of layered-perovskite phase, thin films were rapid-thermally annealed above $720^{\circ}C$ in oxygen atmosphere. As RTA temperature increased, fluorite phase was transformed to layered-perovskite phase. And the change of Nb contents affected dielectric / electrical properties and microstructure. The ferroelectric characteristics of $Sr_{0.7}/B_{2.3}(Ta_{1-x}Nb_x)_2O_9$ thin film were Pr=8.67 $\mu{C}/cm^2$, Ec=62.4kV/cm and $I_{L}=1.4\times10^{-7}A/cm^2$ at the applied voltage of 5V, respectively.