Ma, Xing-Hua Kweon, Sang-Hyo Nahm, Sahn Kang, Chong-Yun Yoon, Seok-Jin Kim, Young-Sik 2024-01-20T02:30:42Z 2024-01-20T02:30:42Z 2021-09-01 2017-02 0955-2219 https://pubs.kist.re.kr/handle/201004/123158 During the synthesis of Bi2Ge3O9 ceramics using Bi2O3 + 3 GeO2 powders, the Bi4Ge3O12 phase was formed at low temperature (<= 800 degrees C). Bi4Ge3O12 preferentially adopted GeO2-excess phase, and this phase was consistently present in the sintered Bi2Ge3O9 ceramic as a secondary phase. Therefore, Bi4Ge3O12 powder was first calcined and subsequently reacted with GeO2 powder to obtain the pure Bi2Ge3O9 ceramic through the following reaction: 1/2B(4)Ge(3)O(12) + 3/2GeO(2) -> Bi2Ge3O9. Formation of the Bi2Ge3O9 phase was initiated at temperature of 850 degrees C. The pure Bi2Ge3O9 ceramic sintered at 875 degrees C for 8 h had a dense microstructure with an average grain size of 2.7 mu m. Furthermore, the pure Bi2Ge3O9 ceramic exhibited promising microwave dielectric properties for the advanced ceramic substrate: epsilon(r) = 9.7, Qxf = 48,573 GHz and tau(f) = -29.5 ppm/degrees C. (C) 2016 Elsevier Ltd. All rights reserved. English ELSEVIER SCI LTD CHEMICAL COMPATIBILITY LTCC APPLICATIONS LUMINESCENCE BI4GE3O12 CRYSTALS MN Synthesis and microwave dielectric properties of Bi2Ge3O9 ceramics for application as advanced ceramic substrate Article 10.1016/j.jeurceramsoc.2016.08.037 1 JOURNAL OF THE EUROPEAN CERAMIC SOCIETY, v.37, no.2, pp.605 - 610 JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 37 2 605 610 scie scopus 000386643900020 2-s2.0-84992206502 Materials Science, Ceramics Materials Science Article CHEMICAL COMPATIBILITY LTCC APPLICATIONS LUMINESCENCE BI4GE3O12 CRYSTALS MN Bi2Ge3O9 ceramics LTCC Microwave dielectric properties Advanced ceramic substrates