Because of the inherent structural flexibility in coupling design and topological arrangement, substrate integrated waveguide (SIW) filter topologies enjoy better out-of-band frequency selectivity and/or in-band phase response with the allocation of finite transmission zeros (FTZs). In the first article in this series, basic design rules and fundamental electrical characteristics have been presented that indicate the superior performances of SIW structures and their filter applications. Advanced design techniques and innovative structure features have recently been reported in a large number of publications. They include cross couplings realized by physical and nonphysical paths and SIW filters with dual-mode or multimode techniques. Miniaturization-enabled techniques including low-temperature cofired ceramic (LTCC) technology have been developed and applied to the development of SIW filters to reduce the size for low-gigahertz applications using nontransverse electromagnetic (non-TEM) modes. Wideband SIW filters, multiband SIW filters, and reconfigurable SIW filters have also been reported by various research groups. This article reviews these advanced and innovative SIW filter technologies, and related examples are presented and discussed.

Substrate Integrated Waveguide Filters: Design Techniques and Structure Innovations

This work presents a new class of microelectromechanical system (MEMS) resonator toward 60 GHz for the fifth-generation (5G) wireless communications. The wide range of the operating frequencies is achieved by resorting to different orders of the antisymmetric Lamb wave modes in a 400-nm-thick Z-cut lithium niobate thin film. The resonance of 55 GHz demonstrated in this work marks the highest operating frequency for piezoelectric electromechanical devices. The fabricated device shows an extracted mechanical $Q$ of 340 and an $f\times Q$ product of $1.87\times 10^{13}$ in a footprint of $2 \times 10^{-3}$ mm2. The performance has shown the strong potential of LiNbO3 antisymmetric mode devices for front-end applications in 5G high-band.

/pdf/10-60-ghz-electromechanical-resonators-using-thin-film-426lh8rzpr.pdf

10–60-GHz Electromechanical Resonators Using Thin-Film Lithium Niobate

This paper introduces a novel tunable SIW filter implemented using PIN diode switching elements The two-pole filter provides six states ranging from 155 GHz to 20 GHz (25% tuning) Fractional bandwidth ranges from 23% – 30% with insertion loss less than 54 dB and return loss greater than 14 dB over the entire tuning range Each SIW cavity is tuned by perturbing via posts connecting or disconnecting to/from the cavity's top metal layer In order to separate the biasing network from the SIW filter, a three-layer PCB is fabricated using Rogers RT/duroid substrates

http://ieeexplore.ieee.org/iel5/5606055/5614756/05616684.pdf

Tunable SIW bandpass filters with PIN diodes

This work presents a Ku-band microelectromechanical systems (MEMS) based 5-bit phase shifter using dc contact single-pole-four-throw (SP4T) and single-pole-double-throw switches. The design is implemented using a coplanar waveguide transmission line. Two individual 2-bit phase shifters and one 1-bit phase shifter are cascaded to develop the complete 5-bit phase shifter. The phase shifters are fabricated on 635- $\mu{\hbox{m}}$ alumina substrate using a surface micromachining process. The 5-bit phase shifter demonstrates an average insertion loss of 2.65 dB in the 13–18-GHz band with a return loss better than 22 dB and average phase error less than 0.68 $^{\circ}$ at 17 GHz. Total area of the fabricated 5-bit phase shifter is ${\hbox{4.7}}\times {\hbox{2.8}}\ {\hbox{mm}}^{2}$ . The reliability of the single-pole-single-throw and SP4T switches show more than 10 million cycles with an RF power of 0.1–2 W. Furthermore, reliability of the MEMS phase shifter is extensively investigated and presented with cold and hot switched conditions. To the best of our knowledge, this is the first reported MEMS 5-bit phase shifter in the literature that has undergone different reliability and qualification testing including 3-axis vibrations.

Reliability Analysis of Ku-Band 5-bit Phase Shifters Using MEMS SP4T and SPDT Switches

Microelectromechanical systems (MEMS) have been familiar in the field of microelectronics and device technology since 1965, when Harvey C. Nathanson invented the first MEMS device (known as the resonant gate transistor). Since that time, MEMS have represented a prominent field for academic research, with simplified implementations of several devices such as sensors, transducers, actuators, and accelerometers being fabricated. According to MEMS technology, all devices could be fabricated using standard integrated circuit (IC) techniques, with the device?s lateral dimensions normally ranging from a maximum of 500 nm to submicron ranges.

Paradigm Phase Shift: RF MEMS Phase Shifters: An Overview

A compact 5-bit digital MEMS phase shifter that employs 3-port RF MEMS switches is designed and fabricated It is based on the switched-line design and totally twenty switches are used Measurements of the 3-port switch indicate an insertion loss of 066dB and an isolation of 233dB at 10GHz The 5-bit MEMS phase shifter are fabricated on 200 mum high resistivity silicon substrates with total size of 7 mm times 4 mm PCM (Process Control Monitor) is applied to control the stability and consistency of the process The phase shifter performed well in X band, with an average 36dB insertion loss and phase shift error less than 5deg at 10GHz

A Compact 5-bit Switched-line Digital MEMS Phase Shifter

This paper describes a novel kind of filter at Ka-band on silicon substrate, which is based on the substrate integrated waveguide (SIW) design and MEMS fabrication process. Inductively coupled plasma (ICP) deep etching is used to form the square via-holes of SIW cavities. A 5-pole micromachined filter is made from rectangular cavities integrated into a silicon substrate and is fed by coplanar waveguide(CPW) transmission-lines through current probes. Measured results show a 0.5 dB loss with a 6.5% bandwidth at a center frequency of 30.9 GHz. The final size of the filter chip is 10.0 mm x 2.7 mm x 0.4 mm. This micromachined filter gives compact size and outstanding performance with relatively mature batch process.

Monolithic silicon micromachined Ka-band filters

A High-Q microwave (K band) MEMS resonator is presented, which empolys substrate integrated waveguide (SIW) and micromachined via-hole arrays by ICP process. Nonradiation dielectric waveguide (NRD) is formed by metal filled via-hole arrays and grounded planes. The three dimensional (3D) high resistivity silicon substrate filled cavity resonator is fed by current probes using CPW line. This monolithic resonator results in low cost, high performance and easy integration with planar cicuits. The measured quality factor is beyond 180 and the resonance frequency is 21GHz.It shows a good agreement with the simulation results. The chip size is only 4.7mm x 4.6mm x 0.5mm. Finally, as an example of applications, a filter using two SIW resonators is designed.

A High-Q Microwave MEMS Resonator

A High-Q microwave (K band) MEMS resonator is presented, which employs substrate integrated waveguide (SIW) and micromachined via-hole arrays by ICP process. Nonradiation dielectric waveguide (NRD) is formed by metal filled via-hole arrays and grounded planes. The three dimensional (3D) high resistivity silicon substrate filled cavity resonator is fed by current probes using CPW line. This monolithic resonator results in low cost, high performance and easy integration with planar circuits. The measured quality factor is beyond 180 and the resonant frequency is 21GHz.It shows a good agreement with the simulation results. The chip size is only 4.7mm×4.6mm×0.5mm. Finally, as an example of applications, a filter using two SIW resonators is designed.

https://hal.archives-ouvertes.fr/hal-00257668/document

This paper presents a micromachined bandpass filter with miniature size that has relatively outstanding performance. A silicon-based eight-order microstrip bandpass filter is fabricated and measured. A novel design method of the interdigital filter that can create two transmission zeros is described. The location of the transmission zeros can be shifted arbitrarily in the stopband. By adjusting the zero location properly, the filter provides much better skirt rejection and lower insertion loss than a conventional microstrip interdigital filter. To reduce the chip size, through-silicon-substratevia-hole is used. Good experimental results are obtained.

Zhang Yong

Papers

A Compact 5-bit Switched-line Digital MEMS Phase Shifter

Monolithic silicon micromachined Ka-band filters

A High-Q Microwave MEMS Resonator

A High-Q Microwave MEMS Resonator

A Ku-BAND NOVEL MICROMACHINED BANDPASS FILTER WITH TWO TRANSMISSION ZEROS