以反應燒結法製備BiNbO4微波介電陶瓷

Preparation of BiNbO4 Microwave Dielectric Ceramics by using a Reaction-Sintering Process

王宗安(Tsung-An Wang)

指導教授 ： 蔡文周

崑山科技大學/工程學院/電子工程研究所/碩士(2010年)

摘要

本研究以反應燒結法製備Bi0.97Ce0.03NbO4 (BCN)與BiNb0.96Sb0.04O4 (BNS4)與BiNb0.95Sb0.05O4 (BNS5)微波介電陶瓷，添加不同含量的燒結促進劑(CuO)並分析其微結構及微波介電特性。在實驗中，我們將粉末混和、球磨後，不經煆燒步驟直接壓模成型進行燒結。在X光繞射分析中顯示在低溫燒結下，其主要生成相為orthorhombic結晶構造的BiNbO4，並有少許triclinic結晶構造的BiNbO4產生，隨著CuO含量和燒結溫度的增加，triclinic晶系的含量也會隨之而增加。BCN2陶瓷中在950℃燒結，持溫時間6小時，可得到最佳密度值6.79 g/cm3，其微波特性為：εr~ 38，Qxf~1691 GHz，τf ~ -4.1 ppm/℃。BNS5陶瓷中在1000℃燒結，持溫時間4小時，可得到最佳密度值7.03 g/cm3，BNS5陶瓷在910℃燒結6小時有較佳的微波特性為: εr=41，Qxf=933 GHz，τf = -8.2 ppm/℃。

關鍵字

BiNbO4 ； 微波介電陶瓷 ； 反應燒結法

並列摘要

Ce-doped BiNbO4 ceramics and Sb-doped ones with CuO addition were prepared by using a reaction-sintering process. X-ray diffraction patterns showed that the ceramics are mainly composed of orthorhombic BiNbO4 structures and a second phase of triclinic BiNbO4 structure is found. With the addition of CuO sintering aids, the sintering temperature can be lowered down 100~ 200℃ while keeping a similar apparent density. However, the triclinic BiNbO4 phase of the samples became more prominent as the CuO content or the sintering temperature increased. Bi0.97Ce0.03NbO4 ceramics, sintered at 950℃ for 6h with 2wt% CuO sintering aids, exhibited a maximum density of 6.79 g/cm3, and their microwave dielectric properties were as following: εr=38, Qxf=1691 GHz, and τf=-4.1 ppm/℃. BiNb0.95Sb0.05O4 ceramics sintered at 1000℃ for 4 h showed an apparent density of 7.03 g/cm3, and the one sintered at 910℃ for 6 h exhibited the following microwave dielectric properties: εr= 41, Qxf = 933 GHz, τf= -8.2 ppm/℃.

並列關鍵字

BiNbO4 ； Microwave Dielectric Ceramics ； Reaction-Sintering Process

參考文獻

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