Microwave dielectric properties of Mg1.8R0.2Al4Si5O18 (R = Mg, Ca, Sr, Ba, Mn, Co, Ni, Cu, Zn) cordierite ceramics and their application for 5G microstrip patch antenna

Novel microwave dielectric ceramics based on CaO–MoO3–La2O3 pseudo‐ternary phase diagram and the design of patch antenna

“…The theoretical dielectric loss (7.25 × 10 −4 ) and the measured dielectric loss (1.29 × 10 −4 ) are of the same order of magnitude. Regarding Ca 3 MoO 6 ceramic, the fitted value of the ε'' (4.06 × 10 −3 ) closely matches the measured value (4.40 × 10 −3 ), while the theoretical Q⋅f (22,376 GHz) is almost equal to the measured Q⋅f (23,801 GHz). The fitted value of ε' (9.76) of Ca 3 MoO 6 slightly underestimates the measured value (ε r , 11.26).…”

“…Using a diamond abrasive, holes were drilled at the feeding position to connect the internal probe to the radiating metal patch. The SMA‐KE port was then soldered to the ceramic substrate, completing the preparation of the antenna. 22 $$$$\begin{equation}{{\mathrm{W}}_{\mathrm{p}}}{\mathrm{\; = \;}}\frac{{\mathrm{c}}}{{{\mathrm{2}}{{\mathrm{f}}_{\mathrm{0}}}}}{\left( {\frac{{{{\mathrm{\varepsilon }}_{\mathrm{r}}}{\mathrm{ + 1}}}}{{\mathrm{2}}}} \right)^{{\mathrm{ - 0}}{\mathrm{.5}}}}\end{equation}$$$$ $$$$\begin{equation}{{\mathrm{L}}_{\mathrm{p}}}{\mathrm{\; = \;}}\frac{{\mathrm{c}}}{{{\mathrm{2}}{f_{\mathrm{0}}}\sqrt {{\varepsilon _{\mathrm{e}}}} }} - {\mathrm{2}}\Delta {\mathrm{L}}\end{equation}$$$$ $$$$\begin{equation}\Delta {\mathrm{L\; = \;0}}{\mathrm{.412h}}\frac{{\left( {{\varepsilon _{\mathrm{e}}}{\mathrm{ + 0}}{\mathrm{.3}}} \right)\left( {\frac{{{{\mathrm{W}}_{\mathrm{p}}}}}{{\mathrm{h}}}{\mathrm{ + 0}}{\mathrm{.264}}} \right)}}{{\left( {{\varepsilon _{\mathrm{e}}} - {\mathrm{0}}{\mathrm{.258}}} \right)\left( {\frac{{{{\mathrm{W}}_{\mathrm{p}}}}}{{\mathrm{h}}}{\mathrm{ + 0}}{\mathrm{.8}}} \right)}}\end{equation}$$$$ …”

Ultralow-Permittivity and Temperature-Stable Ba1–xCaxMg2Al6Si9O30 Dielectric Ceramics for C-Band Patch Antenna Applications

“…Given that the contributing fraction of electronic polarization to relative permittivity is generally less than 60% for inorganic materials, ε r < 4 of dense inorganic ceramics is very rare, and ultralow ε r (4 ≤ ε r ≤ 6) can be detected in Li-, Na-, B-, K-, and Si-based inorganic materials, whereas Li, Na, B, and K elements are unstable in high-temperature circumstance. − The primary progress on ultralow-ε r dense ceramics has been focused on silicates due to their low raw material prices and thermal stability. Cordierite-typed Mg 2 Al 4 Si 5 O 18 -based ceramics, in particular their low ε r and CTE, have been receiving increasing attention because of their high potential for dielectric substrates. − However, the poor sintering behavior (phase transitions) and large negative τ f values limited the applications of Mg 2 Al 4 Si 5 O 18 -based ceramics in high-frequency communication. The improvement of sintering behavior and τ f values could cause the increase of ε r in Mg 2 Al 4 Si 5 O 18 -based ceramics, − and it is a big challenge to co-optimize ε r and τ f of Mg 2 Al 4 Si 5 O 18 -based ceramics.…”

Novel copper borate ceramics with lithium-based sintering aids for LTCC terahertz applications

“…Such properties ensure high speed data transfer due to the reduction in device size, signal delay, cross-talk between signal lines, power consumption, and frequency instability related to temperature fluctuations. 2–8 Potential areas of exploitation for terahertz devices, besides wireless 5G and 6G communication systems, are non-invasive imaging for medical, chemical, biological and security applications, as well as non-destructive electronic package inspection and sensing under harsh conditions.…”