Novel Sr3Y2Ge3O12 microwave ceramics: Sintering behavior, phase composition, microstructure and dielectric properties

Mg/Ti co‐substituted CaSmAlO4‐based microwave dielectric ceramics with temperature stability in a wide temperature range

“…On the other hand, the quality factor of ceramics is also affected by non‐intrinsic losses, such as the second phase, homogeneity, point defects, and many other factors 33–35 . First, the second phase is not found in the physical phase characterization of CaSmAl 1− x (Mg 0.5 Ti 0.5 ) x O 4 (0.1 ≤ x ≤ 0.4) ceramic samples (Figure 2), so the influence of impurity phase can be excluded.…”

“…The effect of Mg/Ti composite ion substitution on the sample quality factor should be considered from both intrinsic and non-intrinsic perspectives. [33][34][35] Considering from the perspective of intrinsic loss, the tetragonal phase CaSmAl 1−x (Mg 0.5 Ti 0.5 ) x O 4 ceramics with K 2 NiF 4 structure are stacked by perovskite layers and rock salt layers. Figure 9 shows a schematic structure of CaSmAlO 4 -based single crystals with Al atoms located at the centers of the oxygen octahedra.…”

“…On the other hand, the quality factor of ceramics is also affected by non-intrinsic losses, such as the second phase, homogeneity, point defects, and many other factors. [33][34][35] First, the second phase is not found in the physical phase characterization of CaSmAl 1−x (Mg 0.5 Ti 0.5 ) x O 4 (0.1 ≤ x ≤ 0.4) ceramic samples (Figure 2), so the influence of impurity phase can be excluded. Second, point defects and nonuniformity at grain boundaries also reduce the quality factor of the ceramics, as can be seen in Figures 5 and 6, where the average grain size is getting larger and the uniformity of grain distribution is negatively affected by increasing substitution.…”

Ultra‐high Quality Factor of (Zn2/3Nb1/3)3+ Co‐substitution MgAl2O4 Microwave Dielectric Ceramics

“…As a result, microwave dielectric ceramics with low dielectric constants and high Qf values have received considerable attention. [4][5][6] To date, low dielectric constant materials such as alumina (Al 2 O 3 ), [7] AB 2 O 4 spinel systems, [8][9][10][11][12] and garnet types [13,14] have been investigated. Among them, the magnesium aluminate (MgAl 2 O 4 ) spinel has attracted significant attention owing to its great potential in low-permittivity microwave ceramics (ε r = 7.9).…”

“…To date, low dielectric constant materials such as alumina (Al 2 O 3 ), [ 7 ] AB 2 O 4 spinel systems, [ 8–12 ] and garnet types [ 13,14 ] have been investigated. Among them, the magnesium aluminate (MgAl 2 O 4 ) spinel has attracted significant attention owing to its great potential in low‐permittivity microwave ceramics ( ε r = 7.9).…”