| Title |
Microwave Dielectric Properties of (1-X)Mg_4Ta_2O_{9-x}TiO_2(X=0, 0.3, 0.4) Ceramics with Sintering Temperature |
| Keywords |
Q× textrm{f} ; Mg_4Ta_2O_{9} ; TiO_2 ; sintering temperature |
| Abstract |
The microwave dielectric properties and microstructure of the (1-x)Mg_4Ta_2O_{9-x}TiO_2(X=0, 0.3, 0.4) ceramic were, investigated. The specimens were prepared by the conventional mixed oxide method with sintering temperature of 1350°C∼1425°C. According to the XRD patterns, the (1-x)Mg_4Ta_2O_{9-x}TiO_2(X=0, 0.3, 0.4) ceramics have the Mg_4Ta_2O_{9} phase(hexagonal). The dielectric constant(ε_γ) and density increased with sintering temperature and mole fraction of x. To improve the quality factor and the temperature coefficient of resonant frequency, TiO_2(ε_{r}=100, Q×f_{r}=40,000GHz, τ_{f}=＋450 ppm/°C) was added in Mg_4Ta_2O_{9} ceramics. In the case of the 0.7Mg_4Ta_2O_{9}-0.3TiO_2 and the 0.6Mg_4Ta_2O_{9}-0.4TiO_2ceramics sintered at 1400°C for 5hr., the microwave dielectric properties were ε_γ=11.72, Q×f_{r}=126,419GHz, τ_{f}=-31.82 ppm/°C and ε_{r}=12.19, Q×f_{r}=109,411GHZ, τ_{f}= -17.21 ppm/°C, respectively. |