鈦酸鋇(BaTiO3)摻雜鈦酸鍶(SrTiO3)研究中，因產生擴散性相變化(Diffuse Phase Transition)常廣為學者研究，本論文主觀察兩者相互擴散後，界面處的變化。在鈦酸鋇多晶表面灑上鈦酸鍶燒結後，發現Sr溶入鈦酸鋇極其緩慢，更進ㄧ步探討Sr溶入鈦酸鋇的擴散機制。
此外，在鈦酸鋇多晶與鈦酸鍶多晶疊層燒結後，發現於鈦酸鋇靠界面處長出很多別於兩者的晶粒，利用x-ray繞射儀證明其組成含有Ba4Ti13O30、Ba2Ti9O20、Ba6Ti17O40與BaTi2O5，由掃描式顯微鏡及energy dispersive spectrometer(EDS)成份分析，說明其為Ba與Sr之間相互擴散殘留下來的TiO2與原BaTiO3產生反應，在穿透式顯微鏡觀察上，分別於鈦酸鋇與鈦酸鍶固溶體層中觀察到擴散性相變化的主因晶核-晶殼結構，更於離界面100 μm處的鈦酸鋇中，看到因Ba擴散較Sr快而產生類似於Kirkendall pore的結構，統整實驗結果確定了這異相晶粒的形成與交互擴散機制。

The pseudo-binary system of BaTiO3-SrTiO3 ceramics offering potential applications in the electronic industry, particularly for the passive components, has been studied for its diffuse phase transition over the temperature range of +150oC and -50oC. This research concentrating on the interdiffusion between two sintered layers of such perovskite is a continuation of study, conducted by this author’s group over the past years. Two-layer BaTiO3-SrTiO3 stacks were sintered at 1300oC and annealed for various time periods to investigate if and how the interdiffusion occurs across the BaTiO3-SrTiO3 interface. Optical microscopy reveals an interface layer consisting of polytitanate second phases, which appear to be large, chunky grains initially. Both results obtained from X-ray diffractometry and micro-chemical analysis using the energy-dispersive spectrometry, equipped with the scanning electron microscopy, suggest that the second phases are: Ba4Ti13O30, Ba2Ti9O20, Ba6Ti17O40 and BaTi2O5. These polytitanates are produced from the solid-state reaction between BaTiO3 and TiO2, which is left behind in the BaTiO3 layer when Ba2+ being the faster diffusion A-site cation have moved across into the SrTiO3 layer in a significantly higher content. The interface phases grow progressively to a coherent second-phase layer upon prolonged annealing for 100 h. It is revealed by the transmission electron microscopy that residual pores, similar to the Kirkendall type in the classical Cu-Zn diffusion couple, generated at ~100 μm away from the interface and located in the BaTiO3 layer. This is attributed to the significantly different lattice diffusivities between two A-cations, i.e. Ba2+ being faster than Sr2+ by approximately three times, with A-site vacancies ( ) created in the grains of the BaTiO3 layer. Together with B-site cation vacancy ( ) and oxygen vacancy ( ), similar to the prismatic loops formed in quenched aluminium, condensation of vacancies via a reverse Schottky defect reaction has formed such Kirkendall-like pores within BaTiO3 grains. Interdiffusion has resulted in forming the solid solutions of (Ba,Sr)TiO3, with Sr2+ being solute cation, and (Sr,Ba)TiO3, with Ba2+ being solute cation, in the initial layers, respectively, and the characteristic core-shell grains responsible for the diffuse-phase transition. A mechanism of how cation diffusion produces the core-shell grains in both layers, modified from Bow (1990) and Liu (1991), is proposed.

Abstract..........................................................................I
摘要................................................................................III
目錄：............................................................................IV
第一章 前言：................................................................1
第二章 原理與文獻回顧：............................................3
2-1鈦酸鋇之晶域(domain)：.......................................3
2-2晶核與晶殻結構(core-shell structure)：............10
2-3理想溶液擴散、鈦酸鋇跟鈦酸鍶相互擴散：......12
2-4 BaO-TiO2之平衡相圖：.......................................18
第三章 實驗步驟：.......................................................21
3-1起始粉末：..............................................................21
3-2試片製程：..............................................................22
3-3觀察設備與前處理：..............................................27
3-3.1 x-ray繞射分析儀：..............................................27
3-3.2光學顯微鏡(OM)與掃描電子顯微鏡(SEM)：...27
3-3.3穿透式電子顯微鏡(TEM)：................................28
第四章 實驗結果：.......................................................30
4-1 BaTiO3未摻雜SrTiO3之研究：...........................30
4-1.1 x-ray繞射分析：..................................................30
4-1.2表面微結構分析：...............................................30
4-1.3內部微結構分析：...............................................34
4-2 BaTiO3摻雜SrTiO3研究：...................................36
4-2.1 x-ray繞射分析：..................................................36
4-2.2表面微結構分析：................................................36
4-2.3內部微結構分析：................................................42
4-3 BaTiO3與SrTiO3疊層界面研究：........................43
4-3.1光學顯微鏡(OM)觀察：........................................44
4-3.2 x-ray繞射分析：...................................................48
4-3.2掃描式電子顯微鏡(SEM)觀察：..........................57
4-3.3穿透式電子顯微鏡(TEM)觀察：..........................75
第五章 結果討論：.........................................................85
第六章 結論：.................................................................91
第七章 未來工作：.........................................................93
參考文獻：......................................................................94
附錄一：砂紙號數對照表..............................................97

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