Multiferroic BiFeO3(BFO) material是目前各研究團對熱門的研究題材，在薄膜方面較容易得到純BFO pervoskite phase。而在傳統固態粉末法製備的BFO無法得到純相，文獻中提出目前製備Bulk 純相BFO之方法，本論文是利用化學共沈法(Chemical Route)製備BFO粉末，以及探討單獨在B site摻雜Cr離子與在A、B site摻雜La、Cr離子時，藉由不同離子改善BFO之電性與磁性。本文分三方面來討論，第一部份討論BFO不同calcine溫度、燒結溫度及持溫時間，以及添加分散劑對結構密度以及電性之影響；第二部分討論單獨在B site摻雜Cr離子(2%、3%、5%、10%)，對BFO晶相、電性及磁性的影響。第三部份討論在A、B site摻雜La、Cr離子(La固定10%，Cr5%、10%、20%)，改善第二部分Cr摻雜所形成之雜相，以及電性及磁性等影響。
經由共沈法製備之BFO粉末，可在450度成相，燒結溫度也可在800度達到高密度。且各溫度在控制燒結氣氛下都可得到單相之BFO。漏電流J依不同方法而有些微差異，漏電流J達到10-6~10-7A/cm2間(1kv/cm)，介電常數有60∼70(10M Hz)。PE曲線顯示鐵電性。而添加Cr離子的BFO雖然漏電流降低2個Order，但是在XRD圖中卻發現BiFeO3＋BiCrO3+Bi2Fe4O9相。介電常數降低3倍左右。摻雜La、Cr離子的BFO，文獻中提出在A site摻雜La可以穩定因B site摻雜物破壞BFO pervoskite結構。第三部分也證實這個結論，但漏電流表現比純BFO大一個Order，尤其(La10%,Cr20%)漏電流更大。Cr5%量測出較佳的鐵電性；在磁性方面，以VSM在外加場15000 Oe底下量測，BFO表現出來是順磁性，反鐵磁在低外加場中表現為順磁。第二部分單獨摻雜Cr也都是順磁，磁化量比純BFO大一些。第三部分量測出鐵磁的磁滯曲線，雖然單獨摻雜La10%也是有磁滯曲線，磁化量也相當。但在矯頑場部分，以摻雜(La,Cr)較大，在15000 Oe 外加場底下，B0.9L0.1FO3矯頑場2Hc=5960 Oe，B0.9L0.1F0.95Cr0.05O3的矯頑場2Hc=11143 Oe，B0.9L0.1F0.9Cr0.1O3的矯頑場2Hc=9755 Oe，B0.9L0.1F0.8Cr0.2O3的矯頑場2Hc=8737 Oe。摻雜La10%,Cr5%時候，有機會改變BFO的磁結構使之變為鐵磁性。且在低電場下也表現出鐵電性。

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