Evaluation of SU8 photo polymer for microwave packaging applications

This paper proposes a series of optimized scalable contact-capacitive radio frequency micro- electro-mechanical systems (RF MEMS) switches for millimeter wave applications. Due to the contact-capacitive topology, the ON-state and OFF-state of the switch can be designed separately to obtain smaller <inline-formula> <tex-math notation="LaTeX">$C_{ON}$ </tex-math></inline-formula> and larger <inline-formula> <tex-math notation="LaTeX">$C_{OFF}$ </tex-math></inline-formula>, which results in high capacitance ratio (<inline-formula> <tex-math notation="LaTeX">$C_{r}$ </tex-math></inline-formula>). The <inline-formula> <tex-math notation="LaTeX">$C_{ON}$ </tex-math></inline-formula> is defined by capacitance of the contacts, and it is optimized for low insertion loss (<inline-formula> <tex-math notation="LaTeX">$IL_{ON}$ </tex-math></inline-formula>). The <inline-formula> <tex-math notation="LaTeX">$C_{OFF}$ </tex-math></inline-formula> is defined by the metal-insulator-metal (MIM) capacitor, and it is designed for working band and scalable performance. The measurements of the fabricated devices show acceptable agreements with design and simulation. The optimized switches perform well with <inline-formula> <tex-math notation="LaTeX">$IL_{ON}$ </tex-math></inline-formula> better than 1.5dB and capacitive ratio about 124. The switches follow scaling rules from 20GHz to 110GHz. Linearity (IIP3) of the switches are tested to be higher than 60dBm, and calculated to be higher than 80dBm. Performances of the switch can be further improved and optimized in the future study.

Radio Frequency Micro Electro Mechanical Systems (RF MEMS) are devices showing exceptional potential to satisfy the demands of emerging RF electronic technologies, including those considered for high-power applications, such as for long distance communication systems. Operation in this regime requires an alternative way of thinking for these devices and, for example, a more accurate control of the pull-in voltage is of major importance due to the self-actuation effect. Therefore, the studies focusing on the features of the moving bridges are of great importance. This work presents the fabrication of a full family of RF MEMS switches suitable for high-power implementations having bridges deposited by Au electroplating and released using purely standard wet processes, as well as a carefully designed experimental study of their pull-in voltage. Depositing the bridge of the high-power RF MEMS by using only a single electroplating step makes the device fabrication easier, whilst the utilization of a purely wet release process is an asset. This method relies on low temperature processes, applicable simultaneously in bridges with various geometrical and perforation details without the need of any specialised infrastructure. The experimentally obtained results suggest that for this technology the bridge thickness is a critical factor for controlling the pull-in characteristics between devices fabricated in the same run. Moreover, it is revealed that for thicker bridges, geometry and hole perforation effects are more pronounced. This technology is therefore suitable for developing RF MEMS where the bridge thickness could be potentially utilized for enabling optimization engineering between devices that should be fabricated in the same run but need to satisfy diverse specifications during their operation.

We report a radio frequency micro electromechanical system (RFMEMS) device integrated with phononic crystals (PnC) that provide a Lamb-wave resonator with frequency-selective heat management, power handling capability, and more efficient electromechanical coupling at ultra high frequency (UHF) and low microwave bands. The integrated device is fabricated in a silicon-on-insulator (SOI) aluminum nitride (AlN) platform and boosts thermal performance by 40%, power handling by 3 dB, and coupling coefficient by three times. Design approach is scalable to higher frequencies.

The regular down scaling in integrated circuits technologies stimulates the development of new solutions to increase the integrated circuit performances. Most efforts on size shrinking have been focused on active devices. Among technical solutions, the design and manufacturing of highly reliable integrated passive devices could be particularly relevant. Indeed, dielectrics thin films are used in a wide range of capacitive devices such as Metal Insulator Metal (MIM) capacitors, Metal Oxide Semiconductor (MOS) capacitor, gate for transistors and Memory applications or Radio Frequency Micro Electro MechanicalSystems(RFMEMS)switchingcapacitors.Theelectrical

Hexagonal Shape radiating patch with reconfigurable characteristics for WiMAX/C/WLAN band is presented which is simulated on RT Duroid5880 substrate and is fed by CPW. Fractional bandwidth of antenna corresponds to 153.62% with high rejection dual band-notch reconfigurable characteristics excluding interfering bands WiMAX (3.30GHz–3.80GHz)/C-Band (3.80GHz–4.20GHz)/WLAN (IEEE802.11a/h/j/n5.15GHz–5.35GHz, 5.25GHz–5.35GHz, 5.47GHz–5.725GHz,5.725GHz–5.825GHz) using radio frequency micro electro mechanical systems (RF MEMS) shunt switch. The proposed antenna exhibits 3.4dBi–6.32dBi gain and 78–94% radiation efficiency. The group delay ≤1.0ns is also maintained in the entire operating band. Good dipole like radiation pattern in E-plane and omni-directional pattern in H-plane is also well maintained in the operating band with less co polarization with compact dimensions of 20 × 22 × 0.782 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> .

Radio frequency micro electromechanical system (RF MEMS) based switches are widely used in microwave and millimeter wave communication systems for their low loss, excellent linearity, low power consumption and compact size compared to other contemporary solid state devices [1]. Surface micromachining technology is typically used to develop different types of single pole multi-throw (SPMT) switches like SPST, SPDT and SP4T. MEMS series and shunt switches are extensively used in SPMT RF switches for multiband selectors, filter banks, reconfigurable antennas and phase shifter applications in transmit/receive modules.

Design, fabrication and characterization of miniature RF MEMS switched capacitor based phase shifter

To determine a micro electro mechanical systems (MEMS) inductor configuration that gives large inductance variations and high Q-factors, air-suspended MEMS inductor configurations are studied: (a) an inductor with two angularly meandered lines, (b) a solenoid inductor with a pair of movable shields, (c) a planar spiral inductor with a patterned shield of different areas, and (d) a planar spiral inductor with a metallic frame of different sizes. The configuration of (a) is shown to give a large inductance variation of 115%. However, its Q-factor is only about 10, and difficulties in fabrication are also expected. The configuration of (b) could be a reasonable engineering solution. The inductance variation is 67%, and the maximum Q-factor is over 22. The solenoidal inductor configuration is thus considered suitable for realizing an RF MEMS variable inductor with large inductance variations and high Q-factors.

RF MEMS (radio frequency micro electro mechanical systems) technology holds great promise for wireless communication and sensor systems. Excellent MEMS switching devices have recently been developed, but because of packaging problems, no commercial integrated product exists. The objective of the ongoing work at CFD Research Corporation (CFDRC) and Morgan Research Corporation (MORGAN) is to develop novel packaging concepts, design tools, and demonstrated RF MEMS packaged devices for high frequency applications.

Smoothing reactors, together with the DC filter banks installed at both ends of the HVDC transmission line constitute the `natural boundary', which leads to significant difference in attenuation characteristic of different frequency components of fault transient signals detected by protection. By means of Hilbert-Huang Transform, which is a kind of non-stationary transient signal processing method, the energy of high frequency components(2000Hz~10kHz) is extracted based on the attenuation characteristic of the line boundary, then a novel algorithm for the non-unit transient-based protection is acquired. Moreover, a protection threshold that is adapt to various lengths of transmission line is obtained by extensive simulation work. Experimental results indicate that the new criteria can identify any internal fault on the whole line and clear it rapidly and credibly, what's more important, the accuracy and reliability of the criteria will not be influenced by the length of the transmission line.

In this paper, fully integrated radio frequency (RF) microelectromechanical system (MEMS) switches with piezoelectric actuation have been proposed, designed, fabricated, and characterized. At a very low operation voltage of 2.5V, reliable and reproducible operation of the fabricated switch was obtained. The proposed RF MEMS switch is comprised of a piezoelectric cantilever actuator with a floated contact electrode and isolated CPW transmission line suspended above the silicon substrate. The measured insertion loss and isolation of the fabricated piezoelectric switch are -0.22 dB and -42dB at a frequency of 2GHz, respectively.

With an increased focus on renewable power generation, dynamic line rating is being investigated as a way to connect the new intermittent generation to the grid without needing to build additional infrastructure. The number of transmission lines available for dynamic line rating depends on the length of each transmission line. The St. Clair curve is typically used by industry to determine the length of transmission lines that are thermally rated. This paper will extend this curve by including reactive power in the calculations. This paper will also demonstrate the effect that changing the capacity of the line due to dynamic line rating has on the length of transmission line that is thermally rated.

An approach is described which allows remote tuning of a probe via a length of transmission line, while retaining nearly ideal efficiency relative to the equivalent locally tuned coil. This preservation of efficiency is accomplished through the principle of "partial local matching." In comparison to common methods of remote tuning which involve half-wavelength cables, or in which a length of transmission line is itself utilized as a tuning element, the partial matching method results in a substantial increase in the efficiency of power transfer to the coil, and therefore increased B1 field intensity and signal-to-noise ratio. Applications in which the use of local variable tuning capacitors is made difficult by either space, accessibility, or environmental considerations should benefit from this method.

A fix frequency (2.4GHz) beam scanning leaky-wave antenna based on composite right/left-handed (CRLH) transmission line (TL) is proposed in this paper. Two Radio Frequency Micro-electromechanical System (RF MEMS) switches have been used and the signal transmitting on the TL is reversible and bidirectional. The variation range of the beam direction can be achieved from -63° to +63°. The effect of series résister of the varactors (been loaded on the TL) is studied. A sample of antenna with 38 units is made using the varactors (BB837). The simulation data is agree with the measured one.

A vertical RF-MEMS (Radio Frequency Micro ElectroMechanical Switch) switch design is proposed in this work that features a shunt capacitive configuration and can operate at a very low actuation voltage. Besides operating on a low switching voltage, the switch behold a small value of insertion loss in Up (ON) state and offers a towering isolation factor in Down (OFF) state. A horizontal structure of bridge membrane is used in the proposed design and the switch function (with ON and OFF operating states) is provided by the vertical movement of this membrane structure that is controlled by the electrostatic actuation technique. The actuation pad is centrally fed by a Coplanar Waveguide structure. The switch performance has been analysed over a wide frequency range from 1 to 40 GHz. For obtaining a 1.5 μm vertical displacement of the bridge membrane, a sheer 3.0 Volts of pull-in voltage (VPI) is required. CoventorWare and HFSSv13 tools are used in this work for designing and analysing the proposed switch. The use of fixed-fixed flexure beam configuration is chosen for switch design. Simulation results showcase excellent RF characteristics with isolation factor of −47 dB (at 32.5 GHz) and insertion loss in range of −0.01 to −1.10 dB (for 1−40 GHz frequency).