Effects of CaTiO3 addition on the microwave dielectric properties and antenna properties of BiVO4 ceramics

Structural Elucidation, Electronic and Microwave Dielectric Properties of Ca(SnxTi1–x)O3, (0 ≤ x ≤ 0.8) Lead-Free Ceramics

“…The average grain size is found to be 3.29, 2.82, 2.39, 1.98, and 1.37 μm for the compositions x = 0.0, 0.2, 0.4, 0.6, and 0.8, respectively, as shown in Figure f. In Figure a, sintered at 1200 °C, the existence of a few larger grains can be seen, which might be attributed to calcium titanate attempting to minimize internal energy by reducing the total space of the grain boundary, resulting in the subsequent grain growth . This means that substituting Sn 4+ for Ti 4+ in the perovskite lattice can demote the grain growth as shown in Figure a–e.…”

LTCC and Bulk Zn4B6O13–Zn2SiO4 Composites for Submillimeter Wave Applications

“…The requirements for such new materials include a low dielectric constant to minimize the signal propagation delay, a low dielectric loss to ensure frequency selectivity and to restrict power consumption, and a low sintering temperature to enable the use of multilayer LTCC/ULTCC (low/ultralow temperature cofired ceramics) technology. Along with the modification of materials with a low dielectric constant, such as silica, borosilicate glasses, cordierite, mullite, forsterite, diopside, willemite, and aluminates [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 ], which have been well-known for decades, less popular ceramics have been explored recently, such as borates, tungstates, molybdates, vanadates, and phosphates [ 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 ]. The use of ceramic-ceramic or glass–ceramic composites is an effective way to tailor microstructure, electric, and thermal properties of functional materials for microwave substrates.…”

Effect of A-site modification on structural and microwave dielectric properties of calcium titanate

“…Two traditional techniques for dielectric ceramic modification with desired features are known: one is to produce a new dielectric ceramic material, and the other is to make a composite utilizing two or more dielectric materials with characteristic compensation. The most common strategy is to combine two or more chemicals with negative and positiveτ f values to achieve nearly equal zero τ f values [6,[9][10][11][12]. For example, 0.95MgTiO3 -0.05CaTiO3 ceramic shows (ε r ) ∼21, (Q × f) ∼56,000 GHz at 7 GHz and τ f ∼ 0 ppm/°C [11].…”

“…In recent work, Bai et al showed the applicability of CaTiO3 for microwave absorption in X and Ku bands [18]. The CaTiO3-based ceramics have been mostly used as one component of the composite materials to get good microwave dielectric properties due to their moderate dielectric value and positive τ f [6,11,12,[19][20][21][22][23][24]. The selection of materials for composite is essential to know its structural and microwave dielectric properties in detail.…”