The Enhanced Thermal Stability of (Mg<sub>0.95</sub>Ni<sub>0.05</sub>)<sub>2</sub>TiO<sub>4</sub> Dielectric Ceramics Modified by a Multi-Phase Method

oleh: Chun-Hsu Shen, Ting-Wei Shen, Tsai-Yu Hsieh, Kai-Chun Lan, Shen-Hsien Hsu, Ching-Hsuan Wang, Yu-Ting Lin, Wen-Fang Wu, Zong-Liang Tseng

Format: Article
Diterbitkan: MDPI AG 2023-04-01

Deskripsi

The thermal stability of (Mg<sub>0.95</sub>Ni<sub>0.05</sub>)<sub>2</sub>TiO<sub>4</sub> dielectric ceramics has been improved by mixing with CaTiO<sub>3</sub> phases owing to higher positive temperature coefficients. The pure (Mg<sub>0.95</sub>Ni<sub>0.05</sub>)<sub>2</sub>TiO<sub>4</sub> and the mixture phase systems of CaTiO<sub>3</sub>-modified (Mg<sub>0.95</sub>Ni<sub>0.05</sub>)<sub>2</sub>TiO<sub>4</sub> were verified by XRD diffraction patterns to ensure the crystallite of different phases. The microstructures of the CaTiO<sub>3</sub>-modified (Mg<sub>0.95</sub>Ni<sub>0.05</sub>)<sub>2</sub>TiO<sub>4</sub> were observed by SEM and EDS to investigate the relation between element ratios and grains. As a result, it can be seen that the thermal stability of the CaTiO<sub>3</sub>-modified (Mg<sub>0.95</sub>Ni<sub>0.05</sub>)<sub>2</sub>TiO<sub>4</sub> can be effectively enhanced, compared with the pure (Mg<sub>0.95</sub>Ni<sub>0.05</sub>)<sub>2</sub>TiO<sub>4</sub>. Moreover, the radio frequency dielectric performances of CaTiO<sub>3</sub>-modified (Mg<sub>0.95</sub>Ni<sub>0.05</sub>)<sub>2</sub>TiO<sub>4</sub> dielectric ceramics are strongly dependent upon the density and the morphology of the specimens. The champion sample with the ratio of (Mg<sub>0.95</sub>Ni<sub>0.05</sub>)<sub>2</sub>TiO<sub>4</sub> and CaTiO<sub>3</sub> of 0.92:0.08 showed an ε<sub>r</sub> value of 19.2, an <i>Qf</i> value of 108,200 GHz, and a τ<i><sub>f</sub></i> value of −4.8 ppm/°C, which may encourage (Mg<sub>0.95</sub>Ni<sub>0.05</sub>)<sub>2</sub>TiO<sub>4</sub> ceramics to broaden the range of novel applications and match the requirements of 5G or next-generation communication systems.