scholarly journals Suppression of Acoustic Resonances in BST-Based Bulk-Ceramic Varactors by Addition of Magnesium Borate

Crystals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 786
Author(s):  
Prannoy Agrawal ◽  
Daniel Kienemund ◽  
Dominik Walk ◽  
Stipo Matic ◽  
Nicole Bohn ◽  
...  
Keyword(s):  
High Power ◽  
Wide Frequency Range ◽  
Q Factor ◽  
Low Loss ◽  
Magnesium Borate ◽  
Power Matching ◽  
Bulk Ceramic ◽  
Low Dielectric ◽  
Ferroelectric Layer ◽  
Acoustic Resonances

This work presents a method for reducing acoustic resonances in ferroelectric barium strontium titanate (BST)-based bulk ceramic varactors, which are capable of operation in high-power matching circuits. Two versions of parallel-plate varactors are manufactured here: one with pure BST and one with 10 vol-% magnesium borate, Mg3B2O6 (MBO). Each varactor includes a 0.85-mm-thick ferroelectric layer. Acoustic resonances that are present in the pure BST varactor are strongly suppressed in the BST-MBO varactor and, hence, the Q-factor is increased over a wide frequency range by the addition of small amounts of a low-dielectric-constant (LDK) MBO. Although the tunability is reduced due to the presence of non-tunable MBO, the increased Q-factor extends the varactor’s availability for low-loss and high-power applications.

Low loss, fully-printed, ferroelectric varactors for high-power impedance matching at low ISM band frequency

2019 ◽  
Vol 11 (7) ◽  
pp. 658-665
Author(s):  
Daniel Kienemund ◽  
Nicole Bohn ◽  
Thomas Fink ◽  
Mike Abrecht ◽  
Walter Bigler ◽  
...  
Keyword(s):  
High Power ◽  
Power Level ◽  
Impedance Matching ◽  
Input Power ◽  
Low Loss ◽  
Band Frequency ◽  
Power Matching ◽  
Metal Insulator Metal ◽  
Ferroelectric Varactors ◽  
Suppression Technique

AbstractLow loss, ferroelectric, fully-printed varactors for high-power matching applications are presented. Piezoelectric-induced acoustic resonances reduce the power handling capabilities of these varactors by lowering the Q-factor at the operational frequency of 13.56 MHz. Here, a quality factor of maximum 142 is achieved with an interference-based acoustic suppression approach utilizing double metal–insulator–metal structures. The varactors show a tunability of maximum 34% at 300 W of input power. At a power level of 1 kW, the acoustic suppression technique greatly reduces the dissipated power by 62% from 37 W of a previous design to 14.2 W. At this power level, the varactors remain tunable with maximum 18.2% and 200 V of biasing voltage.

Design of Small-size and Low-loss LTCC Filters on Capacitively Loaded Cavities

2015 ◽  
Vol 2015 (CICMT) ◽  
pp. 000172-000183
Author(s):  
Viacheslav Turgaliev ◽  
Dmitry Kholodnyak ◽  
Jens Müller ◽  
Matthias A. Hein
Keyword(s):  
High Performance ◽  
Wide Frequency Range ◽  
Microwave Filters ◽  
Dual Band ◽  
Q Factor ◽  
Low Loss ◽  
Lumped Element ◽  
Low Profile ◽  
Compact Size ◽  
Capacitive Loading

Design of microwave filters for portable electronics is complicated by conflicting requirements to be met simultaneously such as high selectivity, low insertion loss and compact size. Substrate integrated waveguide (SIW) technology allows designing low-profile high-Q resonators and low-loss bandpass filters based thereof. However, SIW filters are not well-suited for telecommunication applications because of remarkably large size in plane. The size of a SIW cavity can be dramatically reduced by a capacitive loading. Capacitively loaded cavities (CLCs) operating in the TM110 mode can be as small as 1/8 of the guided wavelength and even smaller, i.e. comparable in size with lumped-element resonators. Although the unloaded Q-factor decreases proportionally to cavity size, miniaturized CLCs can exhibit much higher Q-factor than that of lumped-element resonators. This paves the way for designing small-size and low-loss filters for wireless communications and different applications. Miniaturized capacitively loaded SIW cavities are favorably implemented by means of the low temperature co-fired ceramics (LTCC) technology. The goal of the paper is to demonstrate manifold possibilities and flexibility offered by the LTCC technology to the design of advanced microwave filters on CLCs. Different design and manufacturing aspects are considered. Various design examples of high-performance LTCC resonators and filters for single- and dual-band wireless applications are presented. The designed resonators and filters were manufactured using the commercial DuPont Green Tape 951 LTCC system. The LTCC filters on miniaturized CLCs are shown advantageous with regard to small size, low loss, and absence of spurious response over a wide frequency range.

Role of the Electrode Morphology, Thickness and Orientation in the Ferroelectric Performance of Epitaxial Pb(Zr,Ti)O3 Thin Films

2000 ◽  
Vol 655 ◽  
Author(s):  
Cesar Guerrero ◽  
Florencio Sánchez ◽  
José Roldán ◽  
Frank Güell ◽  
María V. García-Cuenca
Keyword(s):  
Electrode Materials ◽  
Stabilized Zirconia ◽  
Large Thickness ◽  
Low Dielectric ◽  
Thin Film Capacitors ◽  
Pzt Thin Film ◽  
Ferroelectric Layer ◽  
Ferroelectric Capacitors ◽  
Lattice Matched

AbstractA comparison of pulsed laser deposited PbZr0.53Ti0.47O3 (PZT) thin film capacitors with SrRuO3 (SRO) and LaNiO3 (LNO) electrodes on (001) yttria-stabilized zirconia (YSZ) and lattice matched (001) LaAlO3 substrates is presented. Both electrode materials allow for the formation of ferroelectric capacitors with large remnant polarization (20-30 μC/cm2) and negligible fatigue, although slight differences arise regarding the promotion of either the rhombohedral or tetragonal phases of PZT. Far more crucial seems to be the tendency of SrRuO3 to develop a rougher surface at either small (<30 nm) or large thickness (>100 nm), and on YSZ substrates. In those cases a highly defective and possibly low dielectric interface forms between the electrode and the ferroelectric layer, resulting in greatly degraded ferroelectric performance. LaNiO3 is free from these limitations except for the cracks forming at very large thickness (>300 nm), and therefore appears as a more versatile electrode material.

Dielectric-loaded L-band filters for high-power space applications

2021 ◽  
pp. 1-11
Author(s):  
Paolo Vallerotonda ◽  
Fabrizio Cacciamani ◽  
Luca Pelliccia ◽  
Alessandro Cazzorla ◽  
Davide Tiradossi ◽  
...  
Keyword(s):  
High Power ◽  
Dielectric Resonators ◽  
Q Factor ◽  
Rf Power ◽  
Space Applications ◽  
High Q ◽  
Critical Issues ◽  
L Band ◽  
Multipactor Discharge ◽  
Filter Response

Abstract The design and first experimental results of Tx and Rx L-band bandpass filters for a high-power satellite diplexer are presented in this paper. Designed in the framework of an ESA ARTES AT project, the filters are based on TM010 mode dielectric resonators. These resonators allow for better results in terms of volume occupation with respect to other dielectric resonators still maintaining high Q-factor values (>2000). Volume saving above 30% is achieved with respect to standard coaxial filters. The filter geometries and materials have been chosen in order to improve the power-handling and to cope with related critical issues for space applications (i.e. avoid any multipactor discharge in the operating RF power range and low-PIM response). Measurements of Tx filter show good correlation with the design in terms of central frequency, BW, and unloaded Q-factor (almost 3000). Measurements of Rx filter show a worse correlation with the design in terms of filter response shape. This is ascribed to size tolerances of one of the filter resonators. Multiple analyses are ongoing to remove this degradation in the final engineering model.

scholarly journals Low-loss high power RF switching using multifinger AlGaN/GaN MOSHFETs

2002 ◽  
Vol 23 (8) ◽  
pp. 449-451 ◽  
Author(s):  
A. Koudymov ◽  
Xuhong Hu ◽  
K. Simin ◽  
G. Simin ◽  
M. Ali ◽  
...  
Keyword(s):  
High Power ◽  
Low Loss

A Low Loss, High Power Variable Laser Attenuator

2008 ◽  
pp. 93-93-7
Author(s):  
SR Foltyn ◽  
JE Griggs ◽  
LJ Jolin ◽  
JH Roberts ◽  
D Keaton
Keyword(s):  
High Power ◽  
Low Loss

Photosensitive Polyimide having low loss tangent for RF application

2018 ◽  
Vol 2018 (1) ◽  
pp. 000476-000482 ◽  
Author(s):  
Masao Tomikawa ◽  
Hitoshi Araki ◽  
Yohei Kiuchi ◽  
Akira Shimada
Keyword(s):  
Molecular Structure ◽  
Dielectric Constant ◽  
Dielectric Properties ◽  
Dielectric Loss ◽  
High Frequency ◽  
Low Dielectric Constant ◽  
Low Loss ◽  
Elongation At Break ◽  
Low Dielectric ◽  
The Poor

Abstract Progress of 5G telecommunication and mm radar for autopilot, high frequency operation is required. Insulator materials having low loss at high frequency is desired for the applications. We designed the low dielectric constant, and low dielectric loss materials examined molecular structure of the polyimide and found that permittivity 2.6 at 20GHz, dielectric loss 0.002. Furthermore, in consideration of mechanical properties such as the toughness and adhesion to copper from a point of practical use. Dielectric properties largely turned worse when giving photosensitivity. To overcome the poor dielectric properties, we designed the photosensitive system. After all, we successfully obtained 3.5 of dielectric constant and 0.004 of dielectric loss, and 100% of elongation at break. In addition, we offered a B stage sheet as well as varnish. These materials are applicable to re-distribution layer of FO-WLP, Interposer and other RF applications for microelectronics.

scholarly journals A Wideband and Low-Loss Spatial Power Combining Module for mm-Wave High-Power Amplifiers

IEEE Access ◽  
2020 ◽  
Vol 8 ◽  
pp. 194858-194867
Author(s):  
Artem Roev ◽  
Parastoo Taghikhani ◽  
Rob Maaskant ◽  
Christian Fager ◽  
Marianna V. Ivashina
Keyword(s):  
High Power ◽  
Power Amplifiers ◽  
Low Loss ◽  
Power Combining ◽  
Spatial Power Combining
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