Preface. Microelectromechanical Systems (MEMS) and Radio Frequency MEMS. MEMS Materials and Fabrication Techniques. RF MEMS Switches and Micro Relays. MEMS Inductors and Capacitors. Micromachined RF Filters. Micromachined Phase Shifters. Micromachined Transmission Lines and Components. Micromachined Antennae. Integration and Packaging for RF MEMS Devices. Index.

RF MEMS and their applications

This paper presents a 2.2-GHz low jitter sub-sampling based PLL. It uses a phase-detector/charge-pump (PD/CP) that sub-samples the VCO output with the reference clock. In contrast to what happens in a classical PLL, the PD/CP noise is not multiplied by N 2 in this sub-sampling PLL, resulting in a low noise contribution from the PD/CP. Moreover, no frequency divider is needed in the locked state and hence divider noise and power can be eliminated. An added frequency locked loop guarantees correct frequency locking without degenerating jitter performance when in lock. The PLL is implemented in a standard 0.18- ?m CMOS process. It consumes 4.2 mA from a 1.8 V supply and occupies an active area of 0.4 × 0.45 mm2. With a frequency division ratio of 40, the in-band phase noise at 200 kHz offset is measured to be -126 dBc/Hz. The rms PLL output jitter integrated from 10 kHz to 40 MHz is 0.15 ps.

/pdf/a-low-noise-sub-sampling-pll-in-which-divider-noise-is-1i7103ox8p.pdf

A Low Noise Sub-Sampling PLL in Which Divider Noise is Eliminated and PD/CP Noise is Not Multiplied by $N ^{2}$

Wireless communication has led to an explosive growth of emerging consumer and military applications of radio frequency (RF), microwave and millimeter wave circuits and systems. Future personal (hand-held) and ground communications systems as well as communications satellites necessitate the use of highly integrated RF front-ends, featuring small size, low weight, high performance and low cost. Continuing chip scaling has contributed to the extent that off-chip, bulky passive RF components, such as high-Q inductors, ceramic and SAW filters, varactor diodes and discrete PIN diode switches, have become limiting. Micro-machining or MEMS technology is now rapidly emerging as an enabling technology to yield a new generation of high-performance RF-MEMS passives to replace these off-chip passives in wireless communication (sub)systems. This paper reviews the progress in RF-MEMS from a device and integration perspective. The worldwide state-of-the-art of RF-MEMS devices including switches, variable capacitors, resonators and filters are described. Next, it is stipulated how integration of RF-MEMS passives with other passives (as inductors, LC filters, SAW devices, couplers and power dividers) and, active circuitry (ASICs, RFICs) can lead to the so-called RF-MEMS system-in-a-package (RF-MEMS-SiP) modules. The evolution of the RF-MEMS-SiP technology is illustrated using IMEC's microwave multi-layer thin-film MCM-D technology which today already serves as a technology platform for RF-SiP.

https://iopscience.iop.org/article/10.1088/0960-1317/13/4/323/pdf

MEMS for wireless communications: 'from RF-MEMS components to RF-MEMS-SiP'

This letter presents a 60-GHz millimeter-wave on-chip Yagi antenna fabricated with a 0.18-mum CMOS process. A feeding network is designed in a coplanar waveguide (CPW) technology. The 0.18-mum six-metal-layer CMOS process allows the on-chip antenna to utilize a simple CPW-to-coplanar-stripline feed transition and the first metal layer to implement a reflector strip. The CMOS antenna chip size is 1.1 x 0.95 mm2 . A FEM-based 3D full-wave electromagnetic solver, the HFSS, is used for design simulation. The measured antenna input VSWR is less than two from 55 to 65 GHz. The front-to-back ratio of the Yagi antenna is about 9 dB. The measured maximum antenna power gain is about -10 dBi. The simulated antenna radiation efficiency is about 10%.

A 60-GHz Millimeter-Wave CPW-Fed Yagi Antenna Fabricated by Using 0.18- $\mu\hbox{m}$ CMOS Technology

A multiple chip module (MCM) for use with baseband, RF, or IF applications includes a number of active circuit chips having a plurality of different functions. The active circuit chips are mounted on a substrate that is configured to provide an integrated subsystem in a single MCM package. The MCM includes a number of features that enable it to meet electrical performance, high-volume manufacturing, and low-cost requirements. The MCM may incorporate split ground planes to achieve electronic shielding and isolation, vias configured as both thermal sinks and grounding connections, and specifically configured die attach pads and exposed ground conductor pads.

Multiple chip module with integrated RF capabilities

The kinetic of dielectric charging in capacitive RF microelectromechanical systems (RF MEMS) is investigated using an original method of stress and monitoring. This effect is investigated through a new parameter: the shift rate of the actuation voltages. We demonstrate that this lifetime parameter has to be considered as a function of the applied voltage normalized by the contact quality between the bridge and the dielectric. We also demonstrate that this phenomenon is related to Frenkel-Poole conduction, which takes place into the dielectric. We finally propose a model that describes the dielectric charging kinetic in capacitive RF MEMS. This model is used to extract a figure-of-merit of capacitive switches lifetime.

Reliability modeling of capacitive RF MEMS

This paper presents a wideband ohmic shunt switch implemented on a coplanar waveguide (CPW). The switch is fabricated using a dielectric membrane with patterned metallic contacts that short the CPW line when it is electrostatically actuated. The switch has been extrapolated from measurements. It exhibits low insertion loss, good matching, high isolation from DC to W band (>20 dB up to 100 GHz) and very good mechanical properties with switching time <1/spl mu/s.

A DC to 100 GHz high performance ohmic shunt switch

Failure predictive model of capacitive RF-MEMS

This paper reports on the investigation of the kinetic of the dielectric charging in capacitive RF-MEMS through an original method of stress and monitoring. This effect has been investigated through a new parameter that is the shift rate of the actuation voltages (SRAV). We demonstrate that this lifetime parameter has to be considered as a function of the applied voltage normalized by a factor which takes the contact quality between the bridge and the dielectric into account. We also demonstrate that this phenomenon is related to Frenkel-Poole conduction which takes place into the dielectric. We finally propose a model which describes the dielectric charging kinetic in capacitive RF MEMS.

Modeling of the dielectric charging kinetic for capacitive RF-MEMS

This paper presents the fabrication and experimental results of capacitive MEM switches with a carbon nanotubes (CNT) based dielectric for the first time to our knowledge. Double wall nanotubes (DWNT) have been incorporated in the switch silicon nitride dielectric to modify its properties regarding the charging effect. The impact of the CNT density on the MEMS reliability has been demonstrated: a switch lifetime enhancement greater than two orders of magnitude has been achieved.

J.L. Cazaux

Papers

Reliability modeling of capacitive RF MEMS

A DC to 100 GHz high performance ohmic shunt switch

Failure predictive model of capacitive RF-MEMS

Modeling of the dielectric charging kinetic for capacitive RF-MEMS

Carbon Nanotube Based Dielectric for Enhanced RF MEMS Reliability