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This article reports on a low temperature cofired ceramic (LTCC)-based RF MEMS packaging and its electrical modeling using lumped elements and microstrip lines. An LTCC cap with vertical vias was flip-chip bonded with a glass substrate, where a coplanar waveguide (CPW) formed to measure the RF characteristics of packaging structure. We measured return loss (S11) and insertion loss (S21) of the fabricated packaging structure in a frequency range of 1 to 30 GHz. The parameters of two different equivalent circuits using lumped elements and physical microstrip lines were extracted from the measured results. The mean absolute errors (MAEs) were calculated to show the agreement between measured properties and electrical equivalent circuits. The calculated MAEs were 0.591 dB (S11) and 0.146 dB (S21) for lumped elements, and 0.926 dB (S11) and 0.179 dB (S21) for microstrip lines, respectively. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 252–257, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24895

In this article, we proposed the novel monolithic microwave integrated circuit (MMIC) protection technique in plasma etching process for MMIC mounted mechanically movable RF MEMS antenna. We could eliminate the distortion of radiation pattern caused by RF feed line on antenna frame and torsional hinge as using MMIC direct mounting on antenna plate instead of using external RF power source. Silicon-based mechanically movable RF MEMS antenna was released using DRIE process, which was performed on the backside of silicon substrate after MMIC mounting on RF MEMS antenna plate. An aluminum layer on the front side of RF MEMS antenna plays a role of etch stop layer for DRIE process. We measured the radiation pattern as rotating the moving plate along the vertical- and horizontal-direction hinge mechanically. We could obtain the radiation pattern without gain reduction and distortion of radiation pattern. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 3089–3093, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23870

An SU8-quartz composite photoresist has been fabricated and characterized from 1.2 to 1.4 THz; the material contains quartz particles from 0 to 50 wt%. The composite can reduce the inherent losses of SU8 photoresist at terahertz frequencies. Calculated and measured data is presented and compared with SU8 without quartz inclusions. The results show a reduction in losses and an increase in permittivity in the composite material as the density of quartz particles increases. This initial experiment proves the possibility of modifying the electrical parameters of SU8; increasing the quartz density of the composite will modify these parameters further at THz frequencies. (c) 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2329-2330, 2016

In this letter a novel λ/4 micromachined directional coupler is presented with a 10 μm benzocyclobutene (BCB) layer used to suspend one transmission line over another one in order to achieve a 3-dB coupling. The coupler is centered at a frequency of 24 GHz. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1813–1814, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22574