This paper reports a bimorph pinned piezoelectric micromachined ultrasonic transducer (PMUT) for enhanced sound pressure output and electromechanical coupling factor space imaging applications. An equivalent circuit model has been built to analyze the dynamic behavior of PMUTs prototype devices have designed, fabricated. Experimental results show 58% measured increase in pulse-echo measurements 4-meter traveling distance air under 133 kHz driving frequency. As demonstration example,...

The geometric designs of MEMS devices can profoundly impact their physical properties and eventual performances. However, it is challenging for researchers to rationally consider a large number possible designs, as would be very time- resource-consuming study all these cases using numerical simulation. In this paper, we report the use deep learning techniques accelerate design cycle by quickly accurately predicting numerous candidates with vastly different features. Design are represented in...

This paper presents an improved lumped element model for clamped, circular-shape, piezoelectric micromachined ultrasonic transducers (pMUTs). A small signal equivalent circuit is developed to include electrical, mechanical, and acoustic domains, which are analyzed separately combined with the associated couplings. For first time, a two-term mode shape approach adapted reveal intrinsic extrinsic properties of pMUT, such as parameters, input impedance, velocity, displacement, bandwidth,...

This work presents an air-coupled piezoelectric micromachined ultrasonic transducer (pMUT) with high transmitting acoustic pressure by using sputtered potassium sodium niobate (K,Na)NbO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> (KNN) thin film a coefficient (e xmlns:xlink="http://www.w3.org/1999/xlink">31</inf> ~ 8-10 C/m <sup xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) and low dielectric constant (ϵ...

This paper reports an ultrasonic 3D object detector with > 1 meter range based on AlN piezoelectric micromachined transducers (pMUTs) chip. Compared the state-of-art technologies, three distinctive advancements have been achieved: (1) more than 1-meter in sensing distance enabled by a bimorph dual electrode pMUT design; (2) small form factor (6×6 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) and 135° field of view; (3) capability...

We have proposed a phase-shift cancellation scheme to reduce the ring down period of ultrasonic transducers and increase axial resolutions. A piezoelectric micromachined transducer (pMUT) consisting 80 elements with circular diaphragms 415 μm in radius made 2 μm-thick AlN layer has measured resonant frequency 160 kHz. The is minimized by emitting ten pulses followed six additional 180° phase difference. Results show shortened 13% 7.5% for single element 80-element array, respectively. In...

This work presents the sense of touch via non-contact ultrasonic waves by a dual-electrode bimorph piezoelectric micromachined transducer (pMUT) array. The prototype device has 12×12 elements with circular diaphragms 415μm in radius made 2 μm-thick AlN. They are fabricated CMOS compatible micromachining process resulting resonant frequency at 109.4 kHz. Experimentally, best haptic sensation on human fingers is found when emitting high to emulate 100 Hz signals means pulse width modulation...

This work presents the first demonstration of a fully transparent, piezoelectric ultrasonic transducer with 3D printed substrate. All layers transducers were fabricated using optically transparent materials namely: polyvinylidene difluoride (PVDF) for active material, polydimethylsiloxane (PDMS) supporting elastic layer, indium tin oxide (ITO) conductive electrode, and polymethil methacylate (PMMA) as The prototype is 500μm in radius, 100μm thickness 20μm inactive layer. devices used to...

This paper reports a subcutaneous blood pressure (BP) monitoring system with AlN-based, piezoelectric micromachined ultrasonic transducers (PMUTs) on an ambulatory sheep. Compared to the state-of-art, three distinctive achievements have been demonstrated: (1) precision and continuous measurements of from diameter changes vessels as small 2.3 μm by means detections; (2) experimental validations in both vitro artery models acute animal study; (3) first silent without cuff toward fully...

This paper reports the non-contact surface temperature measurements using a single piezoelectric micromachined ultrasonic transducers (pMUTs) array based on time-of-flight (ToF) for first time. Compared with state-of-art technologies, four distinctive advancements have been achieved: (1) sensing via pMUTs by pulse-echo mode to detect changes in ToF; (2) independence material properties, e.g. emissivity; (3) integration an analog frontend both transmitting and receiving; (4) recorded...

This work presents theoretical analysis and finite element simulations of a novel piezoelectric micromachined ultrasonic transducer (pMUT) design. A pMUT with free boundary condition is introduced for the first time compared conventional pMUTs fixed boundary. For same dimensions, proposed design has more than 2.5x electromechanical coupling coefficient to that from traditional clamped due increased mechanical capacitance by edge. The cavity underneath disc behaves as an acoustic resonator....

This paper reports a highly directional air-coupled parametric loudspeaker using single chip of piezoelectric micromachined ultrasonic transducers (pMUTs). Compared with the state-of-art technologies, three distinctive advancements have been achieved: (1) array based on CMOS-compatible bimorph AlN pMUTs; (2) generation audible sound half power beam width less than 5 degrees; and (3) multiple frequency 246 pMUT elements in footprint 13mm by 13mm. As such, proposed could open up new class for...

This work presents the concept, basic theory, fabrication and testing results of non-contact radius curvature (RoC) measurement a surface using piezoelectric micromachined ultrasonic transducers (pMUT). The system is composed minimum three side-by-side transducer arrays <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$4\times 20$</tex> pMUTs with xmlns:xlink="http://www.w3.org/1999/xlink">$208\mu \mathrm{m}$</tex> in diaphragm made...

This paper presents the design, fabrication and tests of a micro-fabricated MEMS 'Chladni' plate resonator. The proposed resonator has square geometry having side length 1400 µm height 35 µm. Its electrode layout are designed to analyze test as many modes possible. is fabricated using silicon-on-insulator process with thick silicon layer on glass substrate. Transverse vibration investigated obtain closed form natural frequencies mode shapes, which derived Rayleigh–Ritz energy method, an...

This paper presents a Lorentz force magnetometer with MEMS resonator structure as sensor. Magnetometer composed of and grill structure. The reduces the heat generation due to current required generate force. proposed sensor is produced standard SOI micromachining processes device layer thickness 35 μm. natural frequency around 83 kHz, Q-factor 1870 at 40 mTorr ambient pressure. Tests are done for 1.12 mT magnetic field in direction normal plane supplied by Maxwell coil. scale factor measured...

Abstract This work presents air-coupled piezoelectric micromachined ultrasonic transducers (pMUTs) with high sound pressure level (SPL) under low-driving voltages by utilizing sputtered potassium sodium niobate K 0.34 Na 0.66 NbO 3 (KNN) films. A prototype single KNN pMUT has been tested to show a resonant frequency at 106.3 kHz 4 V p-p outstanding characteristics: (1) large vibration amplitude of 3.74 μm/V, and (2) acoustic root mean square (RMS) 105.5 dB/V 10 cm, which is 5–10 times higher...

This paper presents the effect of temperature on natural frequency (1,1) mode shape a Resonant MEMS IR bolometer pixel in range 295-340 K. The detector has square plate geometry having side length 1400μm and thickness 35μm. resonating is supported at its geometric center, enabling more robust pixels with fill factor greater than 90% less complicated fabrication process. sensor fabricated using Silicon-On-Glass (SOG) For first time literature, closed form equation to calculate fundamental as...

This work presents the attenuation effect due to surface curvature for ultrasound pulse-echo detection scheme. The magnitude of curved is simulated and experimentally validated by a piezoelectric micromachined transducer (pMUT) array as model with 39 × elements 3 mm 3mm in size made 1 µm-thick A1N layer, 5 urn-thick Si elastic layer. Experimental validations have been conducted measure diameter variations silicone tubes different diameters mineral oil environment mimic acoustic properties...

The most frequently prescribed analgesic drugs in primary care centers Turkey are diclofenac and paracetamol, respectively. In this study, we aimed to compare paracetamol-included prescriptions (PIP) diclofenac-included (DIP) generated for adult patients care.

The tactile-stimulation devices for human fingers vary in design and construction. We are developing MEMS tactile device using cantilever. It is needed improve piezoelectric performance process of development. report film improvement.

Although piezoelectric micromachined ultrasonic transducers (pMUTs) are of great interest for various applications, the current fabrication complexity and acoustic performance such devices could limit their performance. Especially applications involving low voltage electronics, improving bandwidths transduc-ers is an important step. Here, we present a novel pMUT design with cavity its simple strategy. Our approach not only improves bandwidth compared to conventional pMUTs but also eliminates...