鐵電材料由於其電滯效應可用在記憶元件方面，因此本研究將採用一種簡單
的製備方法來降低製備成本，但同時又能夠維持鐵電基本該有的電滯特性，希望日後製程改良可以取代昂貴的脈衝雷射蒸鍍製程。實驗中我們將使用水熱法長出BiFeO3鐵電顆粒，接著使用高絕緣性的高分子PVDF與BiFeO3鐵電顆粒進行複合，而在複合的過程中會外加一個強電場來修正鐵電顆粒內部總電偶極矩方向，使其達到極化量增加來提高此複合鐵電膜的實用性。

Ferroelectric materials have aroused considerable research interest for their important applications in memory devices due to hysteresis effects. In the present
work, we seek a simple method to prepare ferroelectric materials at low cost while maintaining their basic ferroelectric hysteresis effect. We anticipate that the pulsed laser deposition process may be replaced by our improved preparation method in the future. The BiFeO3 particles were synthesized by a hydrothermal method, then
composited with PVDF. An external electric field was then applied to correct the direction of total dipole moment of the particles in the sample preparation process
for enhancing the polarization.

第一章 序論 1
1-1研究動機 1
1-2論文簡介 1
第二章 理論與文獻回顧 2
2-1鐵電材料性質與結構 2
2-1-1 鐵電材料和順電材料結構關係 2
2-1-2 Ferroelectric phase transition 4
2-1-3 BiFeO_3 鐵電結構特性 10
2-2鐵電疲乏(Fatigue) 13
2-3介電擊穿 (Dielectric Breakdown) 15
2-4水熱法(Hydrothermal) 15
第三章 實驗原理與方法 17
3-1 X光繞射(x-ray diffraction) 17
3-2場發射掃描式電子顯微鏡 18
3-3 Sawyer-Tower Circuit 19
3-3-1 電路架構 19
3-3-2 電路誤差原理 20
第四章 實驗結果與分析 27
複合膜動機/原理 27
4-1 BiFeO_3粉末製備與分析 29
4-2複合膜製備與分析 42
4-3 Sawyer-Tower Circuit分析 51
第五章 結論 55
5-1 總結 55
5-2 未來展望 55
References 56

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