本研究探討 CuTiNb2O8(CTN-112)-doped Al2O3的燒結機制。透過 摻 雜 10 vol%的 CTN-112，可以將 Al2O3的自由燒結溫度從 1600 °C降至 1025 °C。
CTN-112與 Al2O3的介面會發生反應，在 CTN-112比例較少的時候形成
CuNb2O6(CN-12)而在比例較多時生成 Cu4TiNb4Ox(CTN-414)，並在 1006-1010 °C反應產生液相加速晶界間的物質傳遞速率，提升 Al2O3的緻密行為。 而 在液
相生成 前的緻密行為來自於 在 Al2O3晶粒 間 富含 Cu、 Ti和 Nb的晶界玻璃膜
(Intergranular glassy film, IGF)結構，晶界膜的出現降低了晶界能，提高了燒結
驅動力，動力學上晶界膜能夠降低晶界移動的活化能，提高晶界的遷移能力。
性質的部分以 10 vol% CTN-112添 加的 Al2O3為最佳 ，介電常數 為 11 而
Q∙fr (Q為品質因子， fr為共振頻率 )為 7577 GHz共振 頻率 為 11 GHz，此系統可
以達到極高的熱導率 17 W/m·K，遠高於目前市面上常見的 低溫共燒陶瓷基板 材
料 (約 2.5 W/ 90 vol% Al2O3+10 vol% CTN-112的 熱膨脹係數 為 5.79 ppm/°C

Effects of crystalline CuTiNb2O8 (CTN-112) addition on densification, and physical properties of Al2O3 have been investigated. With 10 vol% CTN-112 present, the densification temperature of Al2O3 is greatly reduced from >1600oC to 1025oC. This is attributed to an interfacial reaction taking place between CTN-112 and Al2O3, which yields an Cu-Ti-Nb-rich intergranular glassy film (IGF) before the liquid phase of Cu4TiNb4Ox (CTN-414) is formed at 1006-1010oC. The Cu-Ti-Nb-rich IGF provides a faster kinetic route for ions to diffuse, promoting the densification kinetics of Al2O3+CTN-112 composite. A higher densification with increasing CTN-112 content at a given sintering temperature is observed; however, the thermal conductivity, dielectric and mechanical properties of the resulting Al2O3+CTN-112 composites become deteriorated. The binary Al2O3+10 vol% CTN-112 composite densified at 1025oC has a thermal conductivity of 17 Wm-1K-1, dielectric constant of 11 and product (Q·fr) of quality factor (Q) and resonant frequency (fr) of 7,000-8,000 GHz at 11-12 GHz.

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