# Investigation and Research of High-Performance RF MEMS Switches for Use in the 5G RF Front-End Modules

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Methodology of Designing High-Performance Capacitive RF MEMS Switches

- -
- High dielectric constant, ${\epsilon}_{\mathit{d}}$;
- -
- Low dielectric loss tangent, $\mathit{tan}{\delta}_{\mathit{e}}$;
- -
- High resistivity, $\rho $;
- -
- High thermal conductivity, $\mathit{K}$.

- -
- Functional requirements;
- -
- Geometric properties;
- -
- Properties of the material.

- -
- The first material index ${\mathit{M}}_{1}$ = ${\epsilon}_{\mathit{eff}}$ is associated with dielectric loss in the CPW or effective permittivity ${\epsilon}_{\mathit{eff}}$;
- -
- The second material index ${\mathit{M}}_{2}$ = $\mathit{tan}{\delta}_{\mathit{e}}$ is related to the tangent of dielectric loss;
- -
- The third material index ${\mathit{M}}_{3}$ = ${\alpha}_{\Delta}$ and the first performance index ${\mathit{P}}_{1}$ = $\mathit{f}\left({\epsilon}_{\mathit{eff}},\mathit{tan}{\delta}_{\mathit{e}},{\alpha}_{\Delta}\right)$ is the value of dielectric loss or attenuation;
- -
- The fourth material index ${\mathit{M}}_{4}$ = $\rho $ is the loss of RF power in the substrate, while, since the loss level is directly proportional to the electrical resistivity of the substrate material, the second performance index ${\mathit{P}}_{2}$ = $\mathit{f}\left(\rho \right)$ is electrical loss;
- -
- The result of the electrical and thermal resistances of the substrate material induces heating of the substrate material, which means that the fifth material index ${\mathit{M}}_{5}$ = $\frac{\mathit{1}}{\mathit{K}}\rho $ and the third performance index ${\mathit{P}}_{3}$ = $\mathit{f}\left(\frac{\mathit{1}}{\mathit{K}}\rho \right)$ are thermal residual stresses.

- -
- The first material index ${\mathit{M}}_{1}$ = $\sqrt{\mathit{E}}$ is related to the value of the Young’s modulus of the material;
- -
- The second material index ${\mathit{M}}_{2}$ = $\left(\nu \right)$ is related to the value of the Poisson’s ratio of the material;
- -
- The third material index ${\mathit{M}}_{3}$ = $\left({\alpha}_{\mathit{T}}\right)$ is related to the value of the coefficient of thermal expansion of the material;
- -
- The first performance index ${\mathit{P}}_{1}$ = $\mathit{f}\left(\mathit{E},\nu ,{\alpha}_{\mathit{T}}\right)$ is related to the value of the control voltage;
- -
- The fourth material index ${\mathit{M}}_{4}$ = $\left(\rho \right)$ and the second performance index ${\mathit{P}}_{2}$ = $\mathit{f}\left(\rho \right)$ are related to the value of the electrical resistance of the material and the value of the RF loss that occurs;
- -
- The fifth material index ${\mathit{M}}_{5}$ = $\left(\frac{\mathit{1}}{\mathit{K}}\rho \right)$ and the third performance index ${\mathit{P}}_{3}$ = $\mathit{f}\left(\frac{\mathit{1}}{\mathit{K}}\rho \right)$ are related to the thermal conductivity of the material and thermal residual stresses.

- -
- Dielectric constant, ${\epsilon}_{\mathit{r}}$;
- -
- Electrical resistivity, $\rho $;
- -
- Thermal conductivity, $\mathit{K}$;
- -
- Coefficient of thermal expansion, ${\alpha}_{\mathit{T}}$;
- -
- Young’s modulus, $\mathit{E}$.

- -
- The first material index is related to the value of the dielectric constant ${\epsilon}_{\mathit{r}}$ of the material ${\mathit{M}}_{1}$ = $\left(\frac{\mathit{1}}{\sqrt{{\epsilon}_{\mathit{r}}}}\right)$, while the first performance index ${\mathit{P}}_{1}$ = $\mathit{f}\left(\frac{\mathit{1}}{\sqrt{{\epsilon}_{\mathit{r}}}}\right)$ is related to the value of the control voltage;
- -
- The second material index ${\mathit{M}}_{2}$ = $\left(\rho \xb7{\epsilon}_{\mathit{r}}\right)$ is associated with the value of the electrical resistance and the value of the dielectric constant, while the second performance index ${\mathit{P}}_{2}$ = $\mathit{f}\left(\rho ,{\epsilon}_{\mathit{r}}\right)$ is associated with the electric charge of the dielectric layer $\tau $;
- -
- The third material index ${\mathit{M}}_{3}$ = $\left(\mathit{E}\right)$ is associated with the value of Young’s modulus;
- -
- The fourth material index ${\mathit{M}}_{4}$ = $\left({\alpha}_{\mathit{T}}\right)$ is associated with the value of the coefficient of thermal expansion;
- -
- The fifth material index ${\mathit{M}}_{5}$ = $\left(\mathit{K}\right)$ is associated with the value of the thermal conductivity;
- -
- The third performance index ${\mathit{P}}_{3}$ = $\mathit{f}\left(\mathit{E},{\alpha}_{\mathit{T}},\mathit{K}\right)$ is related to the efficiency of thermal stress relaxation of the RF MEMS switch $\Delta \sigma $;
- -
- The sixth material index ${\mathit{M}}_{6}$ = $\left({\epsilon}_{\mathit{r}}\right)$ is related to the value of the dielectric constant, while the fourth performance index ${\mathit{P}}_{4}$ = $\mathit{f}\left({\epsilon}_{\mathit{r}}\right)$ is related to the value of the capacitance ratio ${\mathit{C}}_{\mathit{r}}$ and, accordingly, the EM parameters obtained.

## 3. Proof of Methodology

#### 3.1. Design of Structures

#### 3.1.1. Designs of the Coplanar Waveguide

#### 3.1.2. Designs of the Movable Membranes

#### 3.2. Design of the Actuation Electrodes

#### 3.3. Design of the Elastic Suspension Elements

#### 3.4. Design of the MIM Capacitor

## 4. Manufacturing Process and Experimental Research

## 5. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

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**Figure 4.**Schematic view of the developed capacitive RF MEMS switches: (

**a**) the one-dimensional model of the displacement of the movable membrane during electrostatic activation; (

**b**) the equivalent electrical model.

**Figure 5.**The isometric 3D topology of the developed capacitive RF MEMS switches: (

**a**) switch (A); (

**b**) switch (B).

**Figure 10.**Distribution graph of CPW (A) and CPW (B) from the frequency RF signal: (

**a**,

**b**) the characteristic resistance ${\mathit{Z}}_{0}$ and the VSWR of CPW (A); (

**c**,

**d**) the characteristic resistance ${\mathit{Z}}_{0}$ and the VSWR of CPW (B).

**Figure 14.**Schematic view of the structures of the fixed down actuation electrodes: (

**a**) switch (A); (

**b**) switch (B).

**Figure 15.**The results of EM and transient thermal modeling of CPW (A) and CPW (B) including fixed down actuation electrodes, contact pads and contact lines: (

**a**) switch (A); (

**b**) switch (B).

**Figure 17.**The results of modeling of electromechanical parameters of switch (A): (

**a**) electrostatic displacement and switching time; (

**b**) distribution of mechanical strain and mechanical stress.

**Figure 18.**The results of modeling of electromechanical parameters of switch (B): (

**a**) electrostatic displacement and switching time; (

**b**) distribution of mechanical strain and mechanical stress.

**Figure 19.**Schematic view of the developed additional fixed MIM capacitor: (

**a**) switch (A); (

**b**) switch (B).

**Figure 20.**The results of EM and transient thermal modeling of CPW (A) and CPW (B) including fixed down actuation electrodes, contact pads, contact lines and MIM capacitor: (

**a**) switch (A); (

**b**) switch (B).

**Figure 21.**The results of EM and transient thermal modeling of the developed RF MEMS switch (A): (

**a**) open state; (

**b**) closed state.

**Figure 22.**The results of EM and transient thermal modeling of the developed RF MEMS switch (B): (

**a**) open state; (

**b**) closed state.

**Figure 24.**Photos of the manufacturing process of experimental samples: (

**a**) RF MEMS switch (A); (

**b**) RF MEMS switch (B).

**Figure 25.**The manufactured experimental samples of RF MEMS switches: (

**a**) RF MEMS switch (A); (

**b**) RF MEMS switch (B).

**Figure 26.**The results of the study of electromagnetic parameters of manufactured experimental samples of RF MEMS switch (A) and RF MEMS switch (B): (

**a**) insertion loss in the open state; (

**b**) reflection loss in the open state; (

**c**) isolation in the closed state.

**Figure 27.**Photos of the process of applying capacitor structures in the experimental study of ${\mathrm{TiO}}_{2}$ thin films.

Material | Electrical | Thermal | Coefficient of |
---|---|---|---|

Resistivity, $\mathit{\rho}$, $\mathsf{\Omega}\times \mathbf{m}$ | Conductivity, K, $\mathbf{W}/\mathbf{m}\times \mathbf{K}$ | Thermal Expansion, ${\mathit{\alpha}}_{\mathit{T}}$, $\left({10}^{-6}{{(}^{\circ}\mathbf{C})}^{-1}\right)$ | |

Aluminum | $2.90\phantom{\rule{4.pt}{0ex}}\times {10}^{-8}$ | 222 | 23.6 |

Gold | $2.35\times {10}^{-8}$ | 388 | 14.2 |

Copper | $1.72\times {10}^{-8}$ | 315 | 17 |

Platinum | $10.60\times {10}^{-8}$ | 71 | 9.1 |

Nickel | $9.50\times {10}^{-8}$ | 70 | 13.3 |

Material | Dielectric | Electrical | Thermal | Coefficient of | Dielectric |
---|---|---|---|---|---|

Constant | Resistivity | Conductivity | Thermal Expansion | Loss Tangent | |

${\mathbf{\epsilon}}_{\mathbf{d}}$ | $\mathbf{\rho}$, $\mathbf{\Omega}\mathbf{\times}\mathbf{m}$ | $\mathit{K}$, $\mathbf{W}\mathbf{/}\mathbf{m}\mathbf{\times}\mathbf{K}$ | ${\mathbf{\alpha}}_{\mathit{T}}$, $\mathbf{\left(}{\mathbf{10}}^{\mathbf{-}\mathbf{6}}{{\mathbf{(}}^{\mathbf{\circ}}\mathbf{C}\mathbf{)}}^{\mathbf{-}\mathbf{1}}\mathbf{\right)}$ | $\mathit{tan}{\delta}_{\mathbf{e}}$ | |

Quartz | 3.8 | $7\times {10}^{17}$ | 13.8 | 5.5 | ≈$7.5\times {10}^{-3}$ |

Glass | 5–10 | ≈${10}^{14}$ | 80 | 9 | ≈$2.5\times {10}^{-3}$ |

GaAs | 12.8 | ${10}^{4}$–${10}^{8}$ | 35–50 | 5.73 | ≈$4\times {10}^{-3}$ |

${\mathrm{Al}}_{2}{\mathrm{O}}_{3}$ | 11.3 | $\approx {10}^{13}$ | 50 | 4.7 | $11\times {10}^{-4}$ |

AlN | 9.2 | ≈${10}^{10}$ | 32.1 | 5.27 | $2.1\times {10}^{-3}$ |

BeO | 6.76 | ≈${10}^{11}$ | 33 | 8.9 | $4\times {10}^{-4}$ |

GaN | 8.5 | $7.8\times {10}^{4}$ | 25.3 | 5.27 | ≈${10}^{-2}$ |

InP | 12.4 | ${10}^{4}$ | 68 | 4.6 | $3.2\times {10}^{-2}$ |

LTCC | 7.3 | ${10}^{12}$ | 28 | 5.6 | $7\times {10}^{-4}$ |

SiC | 9.6 | ≈${10}^{6}$ | 20.7 | 11 | $3\times {10}^{-3}$ |

$\mathrm{HR}\phantom{\rule{4.pt}{0ex}}\mathrm{Si}$ | 11.7 | ${10}^{7}$ | 24.7 | 9.2 | ≈${10}^{-3}$ |

Material | Young’s | Poisson’s | Electrical | Thermal | Coefficient of |
---|---|---|---|---|---|

Modulus | Ratio | Resistivity | Conductivity | Thermal Expansion | |

$\mathit{E}\mathbf{,}\mathbf{GPa}$ | $\mathbf{\upsilon}$ | $\mathbf{\rho}$, $\mathbf{\Omega}\mathbf{\times}\mathbf{m}$ | $\mathbf{K}$, $\mathbf{W}\mathbf{/}\mathbf{m}\mathbf{\times}\mathbf{K}$ | ${\mathbf{\alpha}}_{\mathit{T}}$, $\mathbf{\left(}{\mathbf{10}}^{\mathbf{-}\mathbf{6}}{{\mathbf{(}}^{\mathbf{\circ}}\mathbf{C}\mathbf{)}}^{\mathbf{-}\mathbf{1}}\mathbf{\right)}$ | |

Aluminum | 69 | 0.33 | $2.90\times {10}^{-8}$ | 222 | 23.6 |

Gold | 77 | 0.42 | $2.35\times {10}^{-8}$ | 388 | 14.2 |

Copper | 115 | 0.33 | $1.72\times {10}^{-8}$ | 315 | 17 |

Platinum | 171 | 0.39 | $10.60\times {10}^{-8}$ | 71 | 9.1 |

Nickel | 204 | 0.31 | $9.50\times {10}^{-8}$ | 70 | 13.3 |

${\mathrm{Si}}_{3}{\mathrm{N}}_{4}$ | 304 | 0.3 | ∼${10}^{12}$ | 29 | 2.7 |

Mo | 320 | 0.32 | $5.20\times {10}^{-8}$ | 142 | 4.9 |

${\mathrm{Al}}_{2}{\mathrm{O}}_{3}$ | 380 | 0.22 | ∼${10}^{13}$ | 39 | 7.4 |

Material | Dielectric | Electrical | Thermal | Coefficient of | Young’s |
---|---|---|---|---|---|

Constant | Resistivity | Conductivity | Thermal Expansion | Modulus | |

${\mathbf{\epsilon}}_{\mathbf{r}}$ | $\mathbf{\rho}$, $\mathbf{\Omega}\mathbf{\times}\mathbf{m}$ | $\mathit{K}$, $\mathbf{W}\mathbf{/}\mathbf{m}\mathbf{\times}\mathbf{K}$ | ${\mathbf{\alpha}}_{\mathit{T}}$, $\mathbf{\left(}{\mathbf{10}}^{\mathbf{-}\mathbf{6}}{{\mathbf{(}}^{\mathbf{\circ}}\mathbf{C}\mathbf{)}}^{\mathbf{-}\mathbf{1}}\mathbf{\right)}$ | $\mathit{E}$, $\mathbf{GPa}$ | |

$\mathrm{Si}{\mathrm{O}}_{2}$ | 3.8 | $1\times {10}^{14}$ | 1.4 | 5.6 | 71 |

${\mathrm{Si}}_{3}{\mathrm{N}}_{4}$ | 7 | $1\times {10}^{14}$ | 3 | 9 | 304 |

${\mathrm{Al}}_{2}{\mathrm{O}}_{3}$ | 10 | $1.4\times {10}^{14}$ | 39 | 7.4 | 380 |

AlN | 9.14 | $1.1\times {10}^{14}$ | 16 | 7.7 | 330 |

$\mathrm{Hf}{\mathrm{O}}_{2}$ | 25 | $9\times {10}^{13}$ | 1.1 | 6 | 57 |

${\mathrm{Ta}}_{2}{\mathrm{O}}_{5}$ | 22 | $1\times {10}^{7}$ | 8 | 6.3 | 140 |

$\mathrm{Ti}{\mathrm{O}}_{2}$ | 80 | $1\times {10}^{12}$ | 11.7 | 9 | 230 |

BST | 800 | $1\times {10}^{5}$ | 12 | 9.4 | 1000 |

$\mathrm{Zr}{\mathrm{O}}_{2}$ | 25 | $1\times {10}^{11}$ | 3.9 | 9.2 | 200 |

Component | Length, μm | Width, μm | Depth, μm | Material |
---|---|---|---|---|

CPW (A) $\left(\mathrm{G}\phantom{\rule{4.pt}{0ex}}\mathrm{W}\phantom{\rule{4.pt}{0ex}}\mathrm{G}\right)$ | 20 | 100 | 20 | Copper |

Substrate | 650 | 400 | 500 | ${\mathrm{Al}}_{2}{\mathrm{O}}_{3}$ |

CPW (B) $\left(\mathrm{G}\phantom{\rule{4.pt}{0ex}}\mathrm{W}\phantom{\rule{4.pt}{0ex}}\mathrm{G}\right)$ | 15 | 140 | 15 | Copper |

Substrate | 900 | 700 | 500 | ${\mathrm{Al}}_{2}{\mathrm{O}}_{3}$ |

Component | Length, μm | Width, μm | Thickness, μm | Material |
---|---|---|---|---|

$\mathbf{Switch}\left(\mathbf{A}\right)$ | ||||

Movable membrane | 200 | 60 | 1 | |

Left part | 80 | 60 | 1 | Aluminum |

Central part | 40 | 20 | 1 | |

Right part | 80 | 60 | 1 | |

Holes | ||||

Form | Dimensions, μm | ${\Delta}_{\mathbf{1}},\mathsf{\mu}\mathbf{m}$ | ${\Delta}_{\mathbf{2}},\mathsf{\mu}\mathbf{m}$ | Numbers |

Circle | $\mathrm{D}\phantom{\rule{4.pt}{0ex}}=\phantom{\rule{4.pt}{0ex}}4$ | 3 | 7 | 152 |

$\mathbf{Switch}\left(\mathbf{B}\right)$ | ||||

Movable membrane | 200 | 60 | 1 | |

Left part | 60 | 60 | 1 | Aluminum |

Central part | 80 | 20 | 1 | |

Right part | 60 | 60 | 1 | |

Holes | ||||

Form | Dimensions, μm | ${\Delta}_{\mathbf{1}},\mathsf{\mu}\mathbf{m}$ | ${\Delta}_{\mathbf{2}},\mathsf{\mu}\mathbf{m}$ | Numbers |

Square | $4\times 4$ | 6 | 8 | 68 |

Component | Length, μm | Width, μm | Thickness, μm | Material |
---|---|---|---|---|

$\mathbf{Switch}\left(\mathbf{A}\right)$ | ||||

$\mathrm{Zig}\text{-}\mathrm{zag}\phantom{\rule{4.pt}{0ex}}\mathrm{beam}$ | 135 | 80 | 1 | |

${\mathrm{l}}_{\mathrm{b}}$ | 105 | 10 | 1 | |

${\mathrm{l}}_{\mathrm{a}}$ | 30 | 10 | 1 | Aluminum |

$\mathrm{Connection}\phantom{\rule{4.pt}{0ex}}\mathrm{beam}$ | 80 | 10 | 1 | |

$\mathrm{Number}\phantom{\rule{4.pt}{0ex}}\mathrm{of}$ | ||||

$\mathrm{meanders},\phantom{\rule{4.pt}{0ex}}\mathrm{n}\phantom{\rule{4.pt}{0ex}}=\phantom{\rule{4.pt}{0ex}}1$ | ||||

$\mathrm{Air}\phantom{\rule{4.pt}{0ex}}\mathrm{gap},{\mathrm{g}}_{0}=1$ | ||||

${\mathbf{K}}_{\mathbf{eff}},\mathbf{N}/\mathbf{m}$ | ${\mathbf{F}}_{\mathbf{d}},\mathsf{\mu}\mathbf{N}$ | ${\mathbf{V}}_{\mathbf{p}},\mathbf{V}$ | ${\mathbf{t}}_{\mathrm{s}},\mathsf{\mu}\mathbf{s}$ | ${\mathbf{t}}_{\mathrm{r}},\mathsf{\mu}\mathbf{s}$ |

21.52 | 0.175 | 3.5 | 6.35 | 3.1 |

$\mathbf{Switch}\left(\mathbf{B}\right)$ | ||||

$\mathrm{Zig}\text{-}\mathrm{zag}\phantom{\rule{4.pt}{0ex}}\mathrm{beam}$ | 135 | 80 | 1 | |

${\mathrm{l}}_{\mathrm{b}}$ | 105 | 10 | 1 | |

${\mathrm{l}}_{\mathrm{a}}$ | 30 | 10 | 1 | Aluminum |

$\mathrm{Connection}\phantom{\rule{4.pt}{0ex}}\mathrm{beam}$ | 80 | 10 | 1 | |

$\mathrm{Number}\phantom{\rule{4.pt}{0ex}}\mathrm{of}$ | ||||

$\mathrm{meanders},\phantom{\rule{4.pt}{0ex}}\mathrm{n}\phantom{\rule{4.pt}{0ex}}=\phantom{\rule{4.pt}{0ex}}1$ | ||||

$\mathrm{Air}\phantom{\rule{4.pt}{0ex}}\mathrm{gap},{\mathrm{g}}_{0}=1$ | ||||

${\mathbf{K}}_{\mathbf{eff}},\mathbf{N}/\mathbf{m}$ | ${\mathbf{F}}_{\mathbf{d}},\mathsf{\mu}\mathbf{N}$ | ${\mathbf{V}}_{\mathbf{p}},\mathbf{V}$ | ${\mathbf{t}}_{\mathrm{s}},\mathsf{\mu}\mathbf{s}$ | ${\mathbf{t}}_{\mathrm{r}},\mathsf{\mu}\mathbf{s}$ |

19.35 | 0.15 | 5 | 6.5 | 3.2 |

${\mathit{g}}_{0},\mathsf{\mu}\mathbf{m}$ | $\mathit{\delta}$ | ${\mathit{\epsilon}}_{\mathit{r}}$ | ${\mathit{t}}_{\mathit{d}},\mathsf{\mu}\mathbf{m}$ | ${\mathit{C}}_{\mathbf{MIM}},\mathbf{F}$ | ${\mathit{C}}_{\mathbf{MAM}},\mathbf{F}$ | ${\mathit{C}}_{\mathit{r}}$ |
---|---|---|---|---|---|---|

$\mathbf{Switch}\left(\mathbf{A}\right)$ | ||||||

1 | 37.25 | 80 | 0.2 | $5.28\times {10}^{-11}$ | $3.54\times {10}^{-27}$ | 14.901 |

$\mathbf{Switch}\left(\mathbf{B}\right)$ | ||||||

1 | 116.5 | 80 | 0.2 | $1.65\times {10}^{-10}$ | $3.54\times {10}^{-27}$ | 46.601 |

Parameters | [59] | [60] | [61] | [62] | [63] | [64] | This Work |
---|---|---|---|---|---|---|---|

Lateral | Vertical | Lateral | Lateral | Vertical | Latching | Vertical | |

${\mathrm{V}}_{\mathrm{p}}$, V | 57 | 75 | 15 | 32.6 | 26 | 38 | 3.5/5 |

Q | – | – | – | – | – | – | 0.7 |

${\mathrm{d}}_{\mathrm{r}}$ | – | – | – | – | – | – | |

${\mathrm{t}}_{\mathrm{s}}$, μs | 56 | 10 | 120 | – | 25 | 39.5 | 6.35/6.5 |

${\mathrm{t}}_{\mathrm{r}}$, μs | 40 | 5 | 150 | – | 13 | 94.8 | 3.1/3.2 |

${\mathrm{R}}_{\mathrm{c}}$, $\Omega $ | 1.5 | 1–2 | – | – | $\sim 1$ | – | 0.7/0.62 |

${\mathrm{F}}_{\mathrm{range}}$ | Sub | Sub | Sub | 1–10 | DC-30 | DC-20 | S-/ |

6 GHz | 6 GHz | 6 GHz | GHz | GHz | GHz | C-, X-, Ku | |

${\mathrm{C}}_{\mathrm{r}}$ | – | – | – | – | – | – | 14,901/46,601 |

Open state | |||||||

Theoretical | |||||||

${\mathrm{S}}_{11}$, dB | −0.28 | −0.28 | −0.31 | −0.13 | −0.18 | −1.8 | −0.07/−0.16 |

Experiment | |||||||

−0.69/−0.66 | |||||||

(@GHz) | @6 | @6 | @6 | @6 | @2 | @6 | @3.6/@3.4 |

Theoretical | |||||||

${\mathrm{S}}_{12}$, dB | – | – | – | – | – | – | -41.17/-30.8 |

Experiment | |||||||

−28.35/−20.66 | |||||||

(@GHz) | @3.6/@3.4 | ||||||

Closed state | |||||||

Theoretical | |||||||

${\mathrm{S}}_{21}$, dB | −38.4 | −31 | −36 | −24.96 | −38.8 | −33.18 | −42.2/−54.9 |

Experiment | |||||||

−54.77/−52.13 | |||||||

(@GHz) | @6 | @6 | @6 | @6 | @2 | @6 | @3.6/@3.4 |

${\mathrm{P}}_{\mathrm{RF}}$, W | – | – | – | – | – | – | >1 |

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© 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).

## Share and Cite

**MDPI and ACS Style**

Tkachenko, A.; Lysenko, I.; Kovalev, A.
Investigation and Research of High-Performance RF MEMS Switches for Use in the 5G RF Front-End Modules. *Micromachines* **2023**, *14*, 477.
https://doi.org/10.3390/mi14020477

**AMA Style**

Tkachenko A, Lysenko I, Kovalev A.
Investigation and Research of High-Performance RF MEMS Switches for Use in the 5G RF Front-End Modules. *Micromachines*. 2023; 14(2):477.
https://doi.org/10.3390/mi14020477

**Chicago/Turabian Style**

Tkachenko, Alexey, Igor Lysenko, and Andrey Kovalev.
2023. "Investigation and Research of High-Performance RF MEMS Switches for Use in the 5G RF Front-End Modules" *Micromachines* 14, no. 2: 477.
https://doi.org/10.3390/mi14020477