MgO與Mg(OH)2對無煆燒法製備MgTiO3基微波介電陶瓷之影響

Effects of MgO and Mg(OH)2 on MgTiO3-based microwave dielectric ceramics via a non-calcining process

楊松齡(Song-Ling Yang)

指導教授 ： 劉依政

崑山科技大學/工程學院/電子工程研究所/碩士(2008年)

摘要

本論文將探討MgO與Mg(OH)2對無煆燒法製備MgTiO3基微波介電陶瓷之影響，在實驗中我們將粉末混合、球磨後，不經煆燒步驟直接壓模成型，進行燒結。以MgO為原料時， MgTiO3 (MT)、0.95MgTiO3-0.05CaTiO3 (95MCT)和0.97MgTiO3-0.03SrTiO3 (97MST)陶瓷中都有MgTi2O5二次相生成，使用Mg(OH)2取代MgO後，經無煆燒法可獲得不含二次相之MgTiO3+2mol% Mg(OH)2 (MHT2)、0.95MgTiO3-0.05CaTiO3+2mol% Mg(OH)2 (95MHCT2)和0.97MgTiO3- 0.03SrTiO3+2mol% Mg(OH)2 (97MHST2) 陶瓷體。從SEM圖中發現，MHT、95MHCT2和97MHST2陶瓷體均有晶粒異常成長的狀態。MT陶瓷在1300oC燒結2小時可獲得微波介電特性為：εr=19.2、Q×f=76,300GHz (10.3GHz) 和τf=-55.2ppm/oC。MHT2陶瓷在1350oC燒結2小時可獲得微波介電特性為：εr=15.7、Q×f=143,700GHz (11.4GHz) 和τf=-50.4ppm/oC。95MCT陶瓷在1250oC燒結6小時可獲得微波介電特性為：εr=22.6、Q×f=43,000GHz (9.6GHz) 和τf=0ppm/oC。95MHCT2陶瓷在1250oC燒結2小時可獲得微波介電特性為：εr=19.1、Q×f=67,700GHz (10.3GHz) 和τf=-5ppm/oC。97MST陶瓷在1350oC燒結2小時可獲得微波介電特性為：εr=20.8、Q×f=19,400GHz (10GHz) 和τf=1.2ppm/oC。97MHST2陶瓷在1250oC燒結2小時可獲得微波介電特性為：εr=17.4、Q×f=32,200GHz (10.7GHz) 和τf=0.9ppm/oC。

關鍵字

MgTiO3 ； 微波介電陶瓷 ； 無煆燒法

並列摘要

Effects of MgO and Mg(OH)2 on MgTiO3-based microwave dielectric ceramics via a non-calcining process were investigated. Without any calcinations involved, the mixture of raw materials were pressed and sintered directly. MgTi2O5 phase was detected in MgTiO3 (MT)、0.95MgTiO3-0.05CaTiO3 (95MCT) and 0.97MgTiO3-0.03SrTiO3 (97MST) ceramics using MgO. There are no secondary phases in MgTiO3+2mol% Mg(OH)2 (MHT2)、0.95MgTiO3-0.05CaTiO3+2mol% Mg(OH)2 (95MHCT2) and 0.97MgTiO3-0.03SrTiO3+2mol% Mg(OH)2 (97MHST2) ceramics when the Mg(OH)2 is used. Abnormal grains were observed in MHT, 95MHCT2 and 97MHST2 ceramics. The microwave dielectric properties：εr=19.2、Q×f=76,300GHz (10.3GHz) and τf=-55.2ppm/oC were obtained in MT ceramics sintered at 1300oC for 2 h. εr=15.7、Q×f=143,700GHz (11.4GHz) and τf=-50.4ppm/oC were obtained in MHT2 ceramics sintered at 1350oC for 2 h. The microwave dielectric properties：εr=22.6, Q×f=43,000GHz (9.6GHz) and τf=0ppm/oC were obtained in 95MCT ceramics sintered at 1250oC for 6 h. εr=19.1, Q×f=67,700GHz (10.3GHz) and τf=-5ppm/oC were obtained in 95MHCT2 ceramics sintered at 1250oC for 2 h. The microwave dielectric properties：εr=20.8、Q×f=19,400GHz (10GHz) and τf=1.2ppm/oC were obtained in 97MST ceramics sintered at 1350oC for 2 h. εr=17.4, Q×f=32,200GHz (10.7GHz) and τf=0.9ppm/oC were obtained in 97MHST2 ceramics sintered at 1250oC for 2 h.

並列關鍵字

MgTiO3 ； microwave dielectric ceramics ； non-calcining process

參考文獻

[35] 翁敏航、楊茹媛、洪政源、李義傑、洪茂峰, “高介電材料之微波特性量測,” 國家奈米元件實驗室-奈米通訊，11-1, (2004).

[2] S.B. Cohn, “Microwave bandpass filters containing high-Q dielectric resonator,” IEEE Trans. On MTT, MTT-16, p218-217 (1968).

[4] H. Ouchi, S. Kawashima, “Dielectric ceramics for microwave application”, Jpn. J. Appl. Phys., 24, p60-64 (1985).

[5] J.H. Shon, Y. Inaguma, S.O. Yoon, M. Itoh, T. Nakamura, S.J. Yoon, H.J. Kim, “Microwave dielectric characteristics of ilmenite-type titanates with high Q values,” Jpn. J. Appl. Phys., 33, p5466-5470 (1994).

[6] K. Wakino, “Recent development of dielectric resonator materials and filters in Japan,” Ferroelectrics, 91, p69-86 (1989).