本論文利用X-光繞射儀(XRD)和穿透式電子顯微鏡(TEM)觀察了鎂鈮酸鉛(PMN)在1000OC/2h、30MPa軸向壓力下熱壓燒結及氧氣氛退火處理後的序化晶域演變。暗視野(DF)影像及選區繞射圖形(SADP)觀察得知其序化晶域並不隨退火時間增長而有所改變，其尺寸為2-5 nm。
經由SADP觀察，發現除F超晶格繞射點外的其他超晶格繞射點{h+1/2,k+1/2,l}，稱α-spot，其隨著氧氣氛退火時間增長而愈趨明顯，顯示鉛空缺序化程度增加。
藉由電腦軟體計算，顯示F超晶格繞射點及α超晶格繞射點成因分別為B-位置原子有序化及鉛空缺有序化。

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一、簡介 ………………………………………………………………1

二、文獻回顧 …………………………………………………………3
2-1 PMN晶体結構 ………………………………………………….3
2-2 PMN 粉體製備方法 …………………………………………….4
2-3 強電性材料 …………………………………………………….5
2-4 弛緩型強電性材料 …………………………………………….6
2-5 擴散式相變化 ………………………………………………….8
2-6 鉛空缺機構 ……………………………………………………12

三、實驗方法 …………………………………………………………16
3-1 粉體的製作 ……………………………………………………16
3-2 試片的製作 ……………………………………………………17
3-3 脫碳及退火處理 ………………………………………………20
3-4 X光繞射分析 …………………………………………………20
3-5 相對密度量測 …………………………………………………21
3-6 晶粒大小量測 …………………………………………………21
3-7 微結構觀察 ……………………………………………………23
3-7-1 光學顯微鏡及掃瞄式電子顯微鏡 ………………………23
3-7-2 穿透式電子顯微鏡 ………………………………………23

四、實驗結果 …………………………………………………………26
4-1 X光繞射(XRD)分析 ………………………………………….26
4-1-1 粉體製備 …………………………………………………26
4-1-2 PMN熱壓試片之XRD 分析 ………………………………27
4-2 顯微結構分析 …………………………………………………34
4-2-1掃描式電子顯微鏡 ………………………………………34
4-2-2 穿透式電子顯微鏡 ………………………………………39

五、討論 ………………………………………………………………54
5-1 PMN粉體 ………………………………………………………54
5-2 PMN試片之XRD分析 …………………………………………55
5-3 顯微結構 ………………………………………………………56
5-4 超晶格結構 ……………………………………………………56
5-5 鉛空缺機構 ……………………………………………………58

六、結論 ………………………………………………………………62

參考文獻 ………………………………………………………………63


附錄 ……………………………………………………………………68
A-1 Kikuchi map with selected-area diffraction
patterns(SADP) from relevant zone axes
for PMN perovskite. (superlattice spots
of the (h+1/2 k+1/2 l+1/2) type are seen
from zone axes of eq. 101) ……………………………………68
A-2 JOEL 200CX 及 3010AEM 之校正 ………………………………69
A-3 本研究相關化合物之JCPDS 卡 …………………………………71
A-4 Debye-Scherrer照像型X-ray繞射儀晶格常數
外插計算法(Nelson-Riley fountion) ……………………….74
A-5 PMN晶體之理論密度計算 ………………………………………75
A-6 Powder之程式碼 (Matlab) ……………………………………76

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