本實驗以氧化物法合成BNB6T，並以BNB6T為基材做施體及受體的B-site取代摻雜，摻雜三價Al及五價Ta及Nb以控制材料缺陷的方式提升電性表現。此外，以穿透式電子顯微鏡觀察異質摻雜所產生的缺陷對於電域的影響，期望找出BNB6T電場誘發應變的機制。
結果顯示，BNB6T基材及1mol%、2mol%、3mol%異質摻雜的繞射圖形皆無其他雜相，為標準的鈣鈦礦結構，介於R相和T相之間，以R相為主。少量的異質摻雜即會顯著影響電阻率、介電常數、Td、Tm，及影響材料的相變行為。摻雜Al3+會在材料內部產生氧空缺和電洞使漏電流上升、電阻率下降，而摻雜Ta5+ 及Nb5+對電阻率的影響不明顯。在應變方面，施體及受體所以呈現的應變型式不同，施體為蝴蝶曲線，受體則為V曲線，在摻雜1%Nb時有應變最大值0.3%，較BNB6T提升約0.08%。
使用穿透式電子顯微鏡觀察施體及受體摻雜對電域形貌的影響，發現BNB6T的電域形貌以奈米電域為主，有奈米電域團聚成core-shell的結構，而異質摻雜所產生的缺陷會影響電域形貌，摻雜Al3+使部分奈米電域聚集成長程電域，此種由氧空缺誘發的長程電域並不穩定，容易出現、消失或移動。另一方面摻雜Ta5+ 及Nb5+電域結構仍是以奈米電域為主。研究結果顯示材料內部空缺將對改變奈米電域的形貌，呈現出不同的電性表現。
在TEM下觀察BNB6T及Donor摻雜的Ta5+ 、Nb5+，其奈米電域的繞射圖形下常可以觀察到特殊的繞射點拉長成一條直線的形狀效應，比對高解析中子XRD的文獻，可知線型繞射點由對稱結構P4bm及R3c的繞射點組成，但實際的排列方式仍然不明瞭，可能為此類非鉛材料展現大的電場誘發應變的原因，值得進一步深入研究。

In this thesis, we synthesized lead-free piezo-ceramics BNT-6BT by a conventional oxide mixing fabrication process. Then we used BNT-6BT as a matrix doping acceptor and donor to replace B-site, the position of Titanium, to modify the microstructure and electrical properties. The elements we selected are Aluminum which is an acceptor dopant and Tantalum and Niobium which are donor dopants.
In XRD investigation, all of the specimens show perovskite structure peaks mixing with R phase and T phase which reveal that they are still in the MPB region. The peaks are almost no shift in every specimen in which means there are no remarkable phase change.
Although the phase is almost no change, B-site dopants have changed electrical properties remarkably. Aluminum doped BNB6T would decrease the resistivity and increase the Pr and Ec. The S-E curve showed a typical butterfly shape. Doped with Tantalum and Niobium would show similar effects on BNB6T. There is no remarkable change in resistivity in donor doping. The P-E curve would pinch seriously when doping with Tantalum and Niobium. The S-E curve of Tantalum and Niobium doping would show similar V shape. When we doped 1mol% Niobium, there is the maximum strain of 0.3% which is 0.08% higher than BNB6T.
In TEM investigation, we find that the vacancies which are generated from acceptor or donor replacement would influence domain structure largely. Oxygen vacancies generated from Aluminum doped could let the nano domain transform into long range domain. On the other hand, Tantalum and Niobium dopants would show the same domain feature as BNB6T which is nano domain everywhere. In addition, we discover the diffraction pattern of nano domain would show special streaking spots at zone 310 revealing there are P4bm and R3c symmetries mixing in the matrix which generated the nano domain. This kind of mixing symmetries may be the reason of the giant strain in BNT-Based lead-free materials.

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