本實驗以射頻磁控濺鍍機沉積鐵摻雜量分別為0wt%、0.25wt%、0.5wt%、1wt%、2wt%、3wt%和5wt%的Ba0.5Sr0.5TiO3薄膜於Pt/SiO2/Si(100)基板，以MIM結構來製作，進行探討其鐵摻雜對於鈦酸鍶鋇薄膜之結晶相和電性之影響與特性分析，其中鈦酸鍶鋇介電層的膜厚約450nm。
在晶相研究方面，本實驗將以XRD量測，並以Winfit軟體輔助，以及做AFM及SEM量測其薄膜表面粗糙度和薄膜表面形態影像；電性方面將由Agilent4294A阻抗分析儀來做C-V量測，並換算成相對介電常數εr，並以Agilent E5270B電壓電流量測儀來量測I-V關係，觀察其漏電流的大小。
經由I-V量測可得到在鐵摻雜量為0.5wt、1wt%、2wt%有較小的漏電流密度，其中最小的漏電流密度為2wt%的摻雜量，在電場強度100(kV/cm)為5.924×10-8(A/cm2)，但是電容值與相對介電常數卻呈現隨著摻雜量愈多而減少的趨勢；另外根據本實驗AFM與SEM分析結果也顯示在微量摻雜有較低的表面粗糙度，以及較緻密的結晶結構，這也代表著較緻密的結晶有較低的漏電流。

In this study, the Fe-doped Ba0.5Sr0.5TiO3 high dielectric thin films with Fe content of 0wt%, 0.25wt%, 0.5wt%, 1wt%, 2wt%, 3wt%, and 5wt% were deposited by rf magnetron sputter on Pt/SiO2/Si substrates, and MIM structures are fabricated. Discussion and analysis the influence of Fe dopant to the BST thin film with the relation of crystallization and electrical properties.
The crystallization and microstructure were obtained by XRD, AFM and SEM measurement. The electrical properties measurements of C-V were obtained by Agilent4294A impedance analyzer, and calculated the relative dielectric constants, and Agilent E5270B measured the relation of I-V characteristics.
The result of XRD means Fe-doped BST thin films still hold it’s perovskite structure, and the Fe3+ ion substituted the Ti4+ site of BST structure. Doping slightly Fe to the BST thin film leads to more dense of the morphology of SEM measurement, and AFM measurement shows the surface roughness of the film were more smoothly. The electrical properties of I-V relation come to the lowest leakage current appeared in Fe content of 0.5wt%, 1wt%, and 2wt% of BST thin film, with 5.924×10-8(A/cm2) in electric field 100(kV/cm) of 2wt% Fe content sample, but the dielectric constants and capacitance decreased after Fe doping. The more dense film leads to lower leakage current density.

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