RF MEMS ohmic switches for matrix configurations

Two different topologies of radio frequency micro-electro-mechanical system (RF MEMS) series ohmic switches (cantilever and clamped–clamped beams) in coplanar waveguide (CPW) configuration have been characterized by means of DC, environmental, and RF measurements. In particular, on-wafer checks have been followed by RF test after vibration, thermal shocks, and temperature cycles. The devices have been manufactured on high resistivity silicon substrates, as building blocks to be implemented in different single-pole 4-throw (SP4 T), double-pole double-throw (DPDT) configurations, and then integrated in Low Temperature Co-fired Ceramics (LTCC) technology for the realization of large-order Clos 3D networks.

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Effective resistivity extraction of low-loss silicon substrates at millimeter-wave frequencies

International Journal of Microwave and Wireless Technologies ◽

10.1017/s175907872000077x ◽

2020 ◽

Vol 12 (7) ◽

pp. 615-628

Author(s):

Lucas Nyssens ◽

Martin Rack ◽

Jean-Pierre Raskin

Keyword(s):

Millimeter Wave ◽

Coplanar Waveguide ◽

Characteristic Impedance ◽

Wave Radiation ◽

High Resistivity ◽

Silicon Substrates ◽

Dielectric Losses ◽

Effective Resistivity ◽

Novel Method ◽

High Resistivity Silicon

AbstractThe effective resistivity (ρeff) is a figure of merit commonly used to assess the radio-frequency performance of a substrate from the measurements of coplanar waveguide lines. For highly resistive substrates, such as the trap-rich (TR) substrate, the extracted ρeff decreases by several orders of magnitude at millimeter-wave frequencies. The explanation for this decay is twofold. First, the imaginary part of the characteristic impedance ${\rm \lpar \Im }\lpar Z_c\rpar \rpar$ is not well extracted, which leads to an incorrect separation of the total losses among the metal and substrate losses. Second, the original expression of ρeff does not include dielectric losses, which might become non-negligible at millimeter-wave frequencies. This paper solves both issues by presenting a new procedure to extract ρeff and the dielectric losses simultaneously, and by introducing a novel method to correct ${\rm \Im }\lpar {Z_c} \rpar$. Furthermore, it is shown that this extraction method enables the correct extraction of substrate parameters up to 220 GHz of TR and high-resistivity silicon substrates. Finally, the origin of the large extracted value of dielectric loss is discussed in the potential presence of surface roughness and surface wave radiation. Both phenomena are discounted thanks to measurements of an additional reflective structure and a standard impedance substrate.

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RF MEMS Passives on High-Resistivity Silicon Substrates

IEEE Microwave and Wireless Components Letters ◽

10.1109/lmwc.2013.2283857 ◽

2013 ◽

Vol 23 (12) ◽

pp. 632-634 ◽

Cited By ~ 27

Author(s):

Yonghyun Shim ◽

Jean-Pierre Raskin ◽

Cesar Roda Neve ◽

Mina Rais-Zadeh

Keyword(s):

Rf Mems ◽

High Resistivity ◽

Silicon Substrates ◽

High Resistivity Silicon

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A Ku-band RF-MEMS frequency-reconfigurable multimodal bandpass filter

International Journal of Microwave and Wireless Technologies ◽

10.1017/s1759078714000567 ◽

2014 ◽

Vol 6 (3-4) ◽

pp. 277-285 ◽

Cited By ~ 5

Author(s):

Adrián Contreras ◽

Jasmina Casals-Terré ◽

Lluís Pradell ◽

Flavio Giacomozzi ◽

Jacopo Iannacci ◽

...

Keyword(s):

Bandpass Filter ◽

Rf Mems ◽

Coplanar Waveguide ◽

Center Frequency ◽

High Resistivity ◽

Quarter Wavelength ◽

Relative Bandwidth ◽

Insertion Losses ◽

High Resistivity Silicon ◽

Ku Band

In this paper, a uniplanar RF-MEMS second-order bandpass filter with reconfigurable center frequency is presented. It is based on quarter-wavelength slotline resonators and coplanar waveguide (CPW)-to-slotline multimodal immitance inverters (MIIs), which are reconfigured using RF-MEMS switchable CPW air-bridges (SABs). The filter can be adequately explained and designed using multimodal theory and circuit models. A surface micromachining process on high-resistivity silicon substrate was used to fabricate the filter. Experimental results show frequency reconfiguration from 12 to 13 GHz, maintaining the same relative bandwidth, and insertion losses of 4.6 and 4.7 dB, respectively.

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Heterostructures of GaAs and AlAs on Silicon: X-Ray Analysis and Excimer Laser Annealing

MRS Proceedings ◽

10.1557/proc-116-279 ◽

1988 ◽

Vol 116 ◽

Author(s):

A. Georgakilas ◽

M. Fatemi ◽

L. Fotiadis ◽

A. Christou

Keyword(s):

Molecular Beam Epitaxy ◽

Dislocation Density ◽

Excimer Laser ◽

Molecular Beam ◽

Laser Annealing ◽

High Resistivity ◽

Silicon Substrates ◽

Excimer Laser Annealing ◽

X Ray ◽

High Resistivity Silicon

AbstractOne micron thick AlAs/GaAs structures have been deposited by molecular beam epitaxy onto high resistivity silicon substrates. Subsequent to deposition, it is shown that Excimer laser annealing up to 120mJ/cm2 at 248nm improves the GaAs mobility to approximately 2000cm2 /v-s. Dislocation density, however, did not decrease up to 180mJ/cm2 showing that improvement in transport properties may not be accompanied by an associated decrease in dislocation density at the GaAs/Si interface.

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