近年來，積層陶瓷電容器（MLCC）產品的製備，以介電層薄層化為主要趨勢，此乃因為獲得高電容值之MLCC，最有效的方法是降低介電層厚度以增加單位介電層數，因此鈦酸鋇基之陶瓷原料粉末須往奈米範圍發展。在諸多MLCC產品中，以Y5V規格之市場需求超過50%，Y5V之原料係以(Ba1-xCax) (Ti1-y Zry)O3為主要化學組成，其化學計式中之x及y之範圍為0≦x≦0.12， 0.1≦y≦0.18。

　　傳統鈦酸鋇介電陶瓷粉末以固態反應法合成，已無法滿足高品質MLCC之需求。濕式化學合成技術，則具有達成原子尺度之均質混合及可在低溫下合成高純度奈米粉體之優點，已成為製備高品質MLCC之必須途徑。

　　Pechini於1967年利用多官能基醇類如乙二醇為溶劑，將水溶液中以檸檬酸分子螫合之各成份陽離子，以加熱方式進行酯化反應及聚酯反應，形成類似樹脂的前導溶液，之後在600-700℃間煅燒，可獲得單相BaTiO3。

　　一般薄膜的製備可以依照基材的尺寸、薄膜的厚度以及薄膜的型態來選擇製程，以溶膠-凝膠法旋鍍製備薄膜因具有低溫程序及成本低廉等優點，而利用聚合前導物法所製備之前導溶液具有較高之粘度與流變性質，故亦適合以旋鍍方式製備薄膜。

　　本研究利用Pechini聚合前導物法以檸檬酸為螯合劑，與乙二醇產生酯化以及聚合反應後，形成計量比為(Ba0.95Ca0.05)(Ti0.85,Zr0.15)O3粉體之金屬前導溶液及粉體。在前導物形成最終產物的熱分解過程中，發現形成(Ba0.95Ca0.05)(Ti0.85,Zr0.15)O3前之熱分解與BaTiO3相同，可區分為（1）脫水反應；（2）氧化反應；（3）中間相的產生以及（4）最終相的出現與完成。在BaTiO3之合成此過程中有機酸根螯合陽離子會轉變成碳酸根進而與陽離子鍵結而產生中間相，而當加入計量比之Ca、Zr離子，會抑制與有機酸根的螯合，加速與碳酸根反應，且延遲 至700℃後完全生成最終相。

　　在(Ba0.95Ca0.05)(Ti0.85,Zr0.15)O3粉體的性質方面，700℃煅燒4小時後所合成出的粉體，因為具有較高之表面積，所以有明顯的凝聚現象發生，故在配置25 vol%之有機漿料時，須添加3％之BYK-111分散劑以使漿料充份分散而呈現牛頓流體行為，不過在SEM照片仍顯示有聚團存在。若利用(Ba0.95Ca0.05)(Ti0.85,Zr0.15)O3前導溶液進行旋鍍製備薄膜，則在650℃煅燒30分鐘即可產生結晶性良好之薄膜。

　In order to develop next generation multi-layer ceramic capacitors (MLCC), the raw materials and processing technology must fulfill the requirement for thin dielectrics. The demand of Y5V for MLCC in the market is over 50%. The chemical composition of Y5V has the general formula of (Ba1-xCax) (Ti1-y Zry)O3 with 0≦x≦0.12 and 0.1≦y≦0.18.

　Barium titanate powders have traditionally been prepared by the solid-state reaction, which can not achieve modern quality equipments of MLCC. The wet chemical method has the advantages of atomic-scaled mixing and forming high purity nano-powders at low temperature and become a necessary route for high performance MLCC.

　Pechini in 1967 had used citric acid to chelate metal ions in enthylene glycol and heated the solution to induce esterization and polymerization and finally to form the resin-like precursor solution. Calcined between 600℃ and 700℃, a single-phase BaTiO3 was obtained.

　The selection of the thin film processing is based on the size of substrates, thickness of films and form of films. The precursor solution made using Pechini method is suitable for spin coating approach to prepare thin films .
　In this thesis, Pechini method was used to form (Ba0.95Ca0.05)(Ti0.85Zr0.15)O3 powders. Thermal analysis indicated that thermal decomposition of the precursor is composed of four major steps : (1)a dehydration reaction, (2)combustion reactions, (3) intermediate -phase formation, and (4) decarbonation of the intermediate and formation of (Ba0.95Ca0.05)(Ti0.85,Zr0.15)O3. During decomposition, the nature of the bonding will be transferred from carboxylate groups to carbonate bonds. Compared with BaTiO3, the addition of Ca and Zr ions can hold down the reaction of chelation of metal ions and promote bonding between carbonate and metal ions thus delaying the formation of final perovskite phase.

　Because of the high surface area, the agglomeration of (Ba,Ca)(Ti,Zr)O3 nano-powders, which were calcined at 700℃and kept for four hours is very common. The dispersant of BYK-111 at the dosage of 3% should be added to prepare organic slurries of 25 vol% to show Newtonain behavior with the viscosity between 2~4 mPa·s. However, the agglomeration can still be seen under SEM. Under 650℃ sintering for 30 min, a well crystallized and densified thin film of (Ba0.95Ca0.05)(Ti0.85Zr0.15)O3 can be prepared.

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