Gallium nitride (GaN) is a wide bandgap semiconductor material and the most popular after silicon in industry. The prime movers behind this trend are LEDs, microwave, more recently, power electronics. New areas of research also include spintronics nanoribbon transistors, which leverage some unique properties GaN. GaN has electron mobility comparable with silicon, but that three times larger, making it an excellent candidate for high-power applications high-temperature operation. ability to...

We discuss the contribution of phonon interactions in determining upper limit f.Q product micromechanical resonators. There is a perception MEMS community that maximum microresonator limited to ldquofrequency-independent constantrdquo determined by material properties resonator. In this paper, we for frequencies higher than omega <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">tau</sub> = 1/tau, where tau relaxation time, no longer constant but...

With advances in telecommunications, an increasing number of services rely on high data rate spectrum access. These critical include banking, telemedicine, and exchange technical information. As a result, resources are ever-greater demand the radio has become overly crowded. For efficient usage spectrum, smart or cognitive radios sought after. However, current wireless phones can only select few specific bands. In this paper, we discuss advantages reconfigurable not efficiency but also...

This work presents the first comprehensive investigation of phonon-electron interactions in bulk acoustic standing wave (BAW) resonators made from piezoelectric semiconductor (PS) materials. We show that these constitute a significant energy loss mechanism and can set practical limits lower than anharmonic phonon scattering or thermoelastic damping limits. Secondly, we theoretically experimentally demonstrate interactions, under appropriate conditions, result gain manifested as an improved...

This paper reports on tunable 2- and 3-pole bandpass filters with a wide frequency tuning range (tuning ratio >3) constant bandwidth using switchable varactor-tuned resonators. The center is obtained p-i-n diodes to switch in out quarter-wavelength (λ/4) or half-wavelength (λ/2) resonators for low-band high-band modes, without increasing the capacitance of varactors. A combination electric magnetic coupling utilized realize near absolute across range. feed line fixed matching used external...

This paper reports a continuously tunable lumped bandpass filter implemented in third-order coupled resonator configuration. The is fabricated on Borosilicate glass substrate using surface micromachining technology that offers hightunable passive components. Continuous electrostatic tuning achieved three capacitor banks, each consisting of one and switched capacitors with pull-in voltage less than 40 V. center frequency the tuned from 1 GHz down to 600 MHz while maintaining 3-dB bandwidth...

This paper reports on the implementation of miniaturized ultra-wideband filters integrated with tunable notch using a silicon-based passive device technology. An bandpass filter is realized micromachined silicon substrate, showing an insertion loss 1.1 dB, return better than 15 and attenuation more 30 dB at both lower upper stop-bands, spurious-free response up to 40 GHz. The occupies only 2.9 mm 2.4 die area. To address in-band interference issues associated communication, very compact are...

This paper presents the analysis, design, fabrication, and first measured results demonstrating use of gallium nitride (GaN)-based micromechanical resonator arrays as high-sensitivity, low-noise infrared (IR) detectors. The IR sensing mechanism is based on monitoring change in resonance frequency resonators upon near radiation. are characterized for their RF thermal performance exhibit a radiant responsivity 1.68%/W, time constant order 556 μs, an average -1.5% when compared with reference...

In this letter, we report on the design, fabrication, and measured results of a directly heated phase change RF switch (or via) using germanium telluride in four-terminal configuration. The is separate heater path combining advantages vias, such as low power dissipation for transition, indirectly high handling capability. shows an insertion loss less than 0.6 dB isolation higher 20 at frequencies up to GHz, indicating cutoff frequency more 3.7 THz. area only 4 μm× 6 μm, which smaller MEMS...

Phase change materials are attractive candidates for use in ohmic switches as they can be thermally transitioned between amorphous and crystalline states, showing several orders of magnitude resistivity. fast, small form factor, readily integrated with MEMS CMOS electronics. As such, have a great potential implementing next-generation high-speed reconfigurable RF modules. In this paper, we report on the properties germanium tellurium, PC material, its switching applications. Intrinsic...

We report on the characterization of thin-film near and short wavelength infrared absorbers comprised carbon nanotubes dispersed in a polymer. Charged nanodiamond particles are used to effectively uniformly disperse polymer matrix, leading very homogenous film. Using this new technique, we demonstrate an absorption up 95% films with thicknesses . This remarkably high is result low reflection off surface across film thickness. The complex refractive index extracted using effective media...

Abstract The experimental demonstration of aluminum scandium nitride (AlScN)‐on‐cubic silicon carbide (SiC) heterostructure thin film micromachined resonant transducers operating in a high‐temperature environment up to 600 °C is reported. Macroscopic and microscopic vibrations are investigated through combination ultrasensitive laser interferometry techniques Raman spectroscopy. An average linear temperature coefficient resonance frequency (TC f ) &lt;1 ppm −1 within the range from room 200...

A multigigahertz AlGaN/GaN resonant body transistor (RBT) is reported, wherein the mechanical resonance and electrical signal modulation are achieved simultaneously. 175-Å-thick AlGaN layer used as piezoelectric transduction layer, 2-D electron gas present at interface employed bottom electrode well conducting channel. The carrier concentration of channel modulated when device undergoes acoustic strain. quality factor 250 transconductance 25 <formula formulatype="inline"...

This Letter presents an innovative design of electro-optical modulator using germanium telluride (GeTe) phase change material with integrated nano-heater. The refractive index and the electrical conductivity GeTe significantly as goes though crystallographic change. Amorphization crystallization is achieved Joule heating method by passing current through array metal gratings, where fills slits between lines. These also increase contrast amorphous (on) crystalline (off) phases having...

We present the extension of InvenSense fabrication platform to piezoelectric transduction. The newly proposed CMOS-MEMS Integrated Piezoelectric Platform inherits wafer bonding advantages its predecessor, leverages existing semiconductor infrastructure, and is applicable a wide range applications.

Abstract It is shown that a phase change material (PCM), germanium telluride (GeTe), when integrated into subwavelength layered optical cavity, can produce widely tunable reflective colors. the crystallization temperature (Tx) of GeTe dependent on film thickness for thin films less than ≈20 nm, which exploited color tuning. Four colors from same physical structure are demonstrated by electrical heating, through novel and thermal engineering stack includes two layers with only single joule...

Diverse RF passive devices and microelectro- mechanical systems (MEMS) can be monolithically integrated on a high-resistivity silicon (HR-Si) substrate. However, parasitic surface conduction (PSC) at the interface of HR-Si dioxide (SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) passivation layer reduces effective substrate resistivity, which in turn results deterioration device quality factor (Q) non-linearity. Trap-rich has been...

In this paper, we explore the piezoelectric transduction of in-plane flexural-mode silicon resonators with a center frequency in range 1.3-1.6 MHz. A novel technique utilizing oxide-refilled trenches is implemented to achieve efficient temperature compensation. These are encapsulated within resonator body so as protect them during device release process. By using method, demonstrate high-Q (> 19 000) having low coefficient <; 2 ppm/°C and turnover around 90 °C, ideally suited for use an...

Measured results of a four-terminal directly heated RF phase change switch are presented. Germanium telluride (GeTe) is used as the main resistance element, connecting input/output lines. The resistivity GeTe switched between high-resistance amorphous-state value several kΩ and low-resistance crystallized less than 3.9 Ω in 404 μsec using current pulses passing though GeTe. loss this ohmic at ON state 0.5 dB with isolation more 18 frequencies up to 20 GHz, indicating cutoff frequency > 4...

We demonstrate coupled bulk and surface acoustic wave (BAW/SAW) resonators with significantly improved coupling efficiency as compared to SAW only devices. Two sets of stacks are investigated: one uses a thin film piezoelectric material bottom electrode on GaN substrate (i.e., AlN/Mo/GaN) another includes metal Si AlN/Mo/Si). A vibrating BAW transducer induces in the between two interdigitated transducers improving by factor ≥ 8x conventional SAW. The performance BAW/SAW using each...

This paper presents a new implementation of integrated tunable inductors using mutual inductances activated by micromechanical switches. To achieve large tuning range and high quality factor, silver was used as the structural material, silicon selectively removed from backside substrate. Using this method, maximum 47% at 6 GHz is achieved for 1.1 nH inductor fabricated on low-loss polymer membrane. The effect factor characteristic investigated comparing measured result identical various...