Quartz Transducer Research Articles

Evaluating the Removal of Polystyrene Latex Particles Using the Quartz Transducer Ultrasonic Cleaners in the Megahertz Frequency Range

The removal of nanometer-sized particles is necessary along with a shift to microfabrication and highly integrated semiconductor chips. Spray-type ultrasonic cleaning methods are currently used to clean semiconductors. However, this method has the problem of collapsing wiring patterns due to severe fluctuations in the sound pressure impinging on the substrate surface. We developed a quartz transducer ultrasonic cleaner (QTC) to solve the problem of constant variations in sound pressure. In this study, we conducted experiments on the removal polystyrene latex particles from the surface of silicon wafers using QTC and elucidated the physical particle removal mechanism.

Using Highly Sensitive Piezo Sensors in an Open System for the Diagnostic Analysis of Skin Volatile Substances

A single sensor with a piezoelectric quartz transducer is considered a platform for simulating an “electronic nose” that performs the function of a sensor array. The analytical task was to detect volatile organic compounds, component-by-component, in biosamples at diagnostically relevant concentrations without selecting mixtures or any sample preparation. We confirmed the fundamental possibility of utilizing a single sensor for the separate detection (recognition) of vapors of organic compounds and various functional states of a body during a short contact (60–80 s) with skin, the most representative and constantly performing bioassay. Modifying the electrodes of bulk acoustic wave piezoelectric quartz resonators with 2–4 μg of the nanohydroxyapatite phase is an essential step in solving the problem. The newly calculated adsorption kinetic parameters can be used to detect biomarkers of many diseases with high reliability, including С3–С5 alcohols, ketones, linear and cyclic amines, acids, aldehydes, etc. The hydroxyapatite sensor can detect molecules pointing to problems with many organs, and any abnormalities in the functioning of the nervous and cardiovascular systems. It can also measure the body’s responses and compensatory mechanisms in relation to stress, hunger, and fatigue. The sensor has a potential as a simple diagnostic and monitoring tool for point-of-care diagnostics of both adults and children.

Toward the realization of a primary low-pressure standard using a superconducting microwave resonator.

We describe a primary gas pressure standard based on the measurement of the refractive index of helium gas using a microwave resonant cavity in the range between 500Pa and 20kPa. To operate in this range, the sensitivity of the microwave refractive gas manometer (MRGM) to low-pressure variations is substantially enhanced by a niobium coating of the resonator surface, which becomes superconducting at temperatures below 9K, allowing one to achieve a frequency resolution of about 0.3Hz at 5.2GHz, corresponding to a pressure resolution below 3 mPa at 20Pa. The determination of helium pressure requires precise thermometry but is favored by the remarkable accuracy achieved by ab initio calculations of the thermodynamic and electromagnetic properties of the gas. The overall standard uncertainty of the MRGM is estimated to be of the order of 0.04%, corresponding to 0.2Pa at 500 and 8.1Pa at 20kPa, with major contributions from thermometry and the repeatability of microwave frequency measurements. A direct comparison of the pressures realized by the MRGM with the reference provided by a traceable quartz transducer shows relative pressure differences between 0.025% at 20kPa and -1.4% at 500Pa.

Study of coupling-of-modes for wavelet transform processors using surface acoustic wave devices

To accurately evaluate selected parameters of wavelet transform processors (WTPs) using surface acoustic wave (SAW) devices, a model of WTPs based on coupling-of-modes theory is proposed, and the second-order effects, such as electrode reflection, propagation loss, electrode resistance, acoustoelectric conversion and transducer static capacity, are sufficiently taken into account in the model. The admittance matrix, bandwidth, and insertion loss of WTPs are analyzed by combining the two-port electrical network and coupling-of-modes with the P-matrix based on the wavelet transform processors principle. Wavelet transform processors samples with a piezoelectric substrate of ST-X cut quartz and interdigital transducers (IDTs) material of Al thin film were manufactured with a center frequency of 60.0 MHz and a scale of 0.25 to validate the effect of the model. A comparison of the simulated and measured results found that the relative error of the center frequency was 0.57%, the highest relative error of the bandwidth was 4.51%, and the relative error of the insertion loss was 1.24%. The experimental results show that the model is extremely accurate in effective frequency band, and its application will undoubtedly speed up the process of designing and producing wavelet transform processors while also boosting the utilization of wavelet technology throughout industry.

Paul Langevin, U-boats, and ultrasonics

Created in 1917 to detect German U-boats, Paul Langevin’s piezoelectric quartz transducer remains the foundation of all modern ultrasonic techniques.

From sonar to medical ultrasound—The impact of Paul Langevin

The technical developments and discoveries of Paul Langevin figuratively and literally powered an incredible spectrum of scientific achievement. The quartz transducer technology of his 1918 patent (Procédé et appareils d'émission et de réception des ondes élastiques sous-marines à l'aide des propriétés piézo-électriques du quartz. – French Patent No. 505,703) enabled a level of acoustic output power generally unavailable at ultrasonic frequencies along with an increase in detection sensitivity. While there were disputes as to who should have been included on this patent, its effect on the field of ultrasonics is clear. The impetus for this work was largely high-power sonar for military application but his reported observations of effects on fish and even humans ushered in a new era of ultrasound bioeffects investigations including those of the famous Loomis Laboratory and numerous others. This is arguably the genesis of the rich tradition of research in ultrasound bioeffects and helped drive the pursuit of diagnostic and therapeutic applications of ultrasound including work by such famous researchers as the Fry Brothers. This presentation will review the evolution of bioeffects from the Langevin’s work and its impact on the field of medical ultrasound.

Langevin’s ultrasonics

Langevin’s work in ultrasonics, which resulted in about twenty publications and patents, will be reviewed. At the beginning of WWI, encouraged by Marie Curie, he started work on a directional ultrasonic system to detect submarines and for underwater communications, based on Chilowski’s proposal. Rejecting whistles, sirens and magnetic sources, he used a large mica ‘singing’ condenser for transmission, and proposed a large area carbon granule microphone as receiver. Noise problems with carbon receivers led Langevin, in early 1917, to test a single large slice of quartz, cut perpendicularly to one of its three electrical axes. This orientation differed from that used by Jacques and Pierre Curie’s quartz piezo-électrique, in which the stress and electrical axes are perpendicular. Later that year he demonstrated quartz as a transmitter, creating the enabling technology for later ultrasonic developments. The knowledge was freely disseminated to other Allied laboratories. After the war, Langevin gave the first ever course on theoretical and practical ultrasonics. He facilitated the technological transfer of pulse-echo technology from military to civil sectors and the establishment of a laboratory in Toulon for the certification of ultrasonic transducers. His co-workers went on to study magneto-strictive and high-frequency quartz transducers, therapeutic applications, and finite-amplitude propagation.

Chen system-based chaotic transceiver for frequency output quartz transducers

The application of unidirectional synchronization of two coupled Chen systems is exhibited in this work. In spite of the high dependence on initial conditions, which means that two initially close phase trajectories with time become uncorrelated, it is possible to synchronize two dynamic systems to make them evolve identically. Data transmission using chaos requires mixing an information signal with a chaotic carrier. This procedure performs data encryption and spreads the spectrum of an information signal, which increases information security and reliability. Thus, the prospect of using devices with chaotic dynamics in modern telecommunication and telemetry applications is due to several factors, including high information capacity, various frequencies, and confidentiality of messages. The proposed scheme is considered to be used in a measuring transducer design that requires sensors to operate at a long distance from the rest of the scheme. We propose an application of a chaotic oscillator as a transceiver module for a quarts sensor transducer, which could be used in a telemetry application. The process of producing non-periodic but determined oscillations by the non-linear Chen system and signal transmission application, based on it, are the subject of the research. The complete synchronization of two unidirectionally connected Chen systems and its signal transmission application are considered. The goal is to develop a transceiver extension for the quartz measuring transducer scheme to ensure the stable operation of sensors at a long distance from the rest of the scheme. The result of the research: a chaos synchronization scheme was applied to transmit a frequency-modulated signal, obtained from a difference-frequency block of the quartz sensor transducer. Additionally, the mathematical model and numerical modeling of the Chen dynamical system has been done. The numerical solution of the system's differential equations was obtained using Matlab software. To study the change in the dynamic regime depending on the parameters of the model, the spectrum of Lyapunov exponents was calculated and bifurcation diagrams were constructed. The circuit design of the Chen oscillator was built using Multisim software, which uses the PSpice model to simulate electrical components. A model of an analog signal transmission system with chaotic mixing of a frequency output signal with a chaotic carrier has been proposed as an extension of the use of quartz transducers in measuring devices.

Measurement of complex shear viscosity up to 3 GHz using an electrodeless AT-cut quartz transducer

An experimental method is proposed to determine the frequency-dependent complex shear viscosity of liquids based on the quartz crystal microbalance with dissipation method. An AT-cut quartz transducer without metal electrodes is immersed in a sample liquid and the transducer is electrically coupled to the circuit through the dielectric response of the sample itself. After correcting for the apparent change in the resonance properties due to the dielectric coupling of the sample, our method is able to determine the viscosity of liquids of high polarity and low viscosity at frequencies as high as 3 GHz. The method was then applied to ethylene glycol and the viscoelastic relaxation in the GHz regime was observed. Furthermore, it was also applied to room-temperature ionic liquids to show that the dielectric correction of the resonance properties is valid for conductive liquids.

Nonlinear scattering of crossed ultrasonic beams in the presence of a turbulent bubbly jet flow in water

Experiments involve the nonlinear scattering of mutually perpendicular crossed ultrasonic beams of primary CW frequency components: f1 = 2.240 MHz, f2 = 2.293 MHz; interacting nonlinearly with turbulent bubbly shear flow generated by a circular water jet (nozzle exit diameter D = 1.6 mm and volume flow rate 32 cc/s). The jet axis is perpendicular to the crossed beam axes. The nozzle exit is downward (5 mm above the surface). The water pump’s suction port was at the bottom center of the 10 cm cubic acrylic water tank (wall thickness 4.8 mm). Identical 1.27 cm diameter quartz transducers (T1 and T2) were epoxied at the centers of adjacent vertical tank sidewalls generate the primary beams (in the i or j directions). Identical 4.5MHz receiving transducers (6.35 mm diam PZT-4) measure nonlinear scattering in the forward or backscattered directions. Receiver Rf located in the plane formed by the primary acoustic beam axes) detects in the i cos 45 + j sin 45 direction. Receiver Rb was located in the opposite direction. In the absence of turbulence virtually no radiated sum frequency component exists. Doppler shift, frequency broadening, skewness and kurtosis from the received sum frequency power spectrum were measured.

Elastic and attenuation behavior of the Bi1-x Re x FeO3 (x = 0 & 0.1; Re = La, Pr, Nd & Sm) multiferroic system

ABSTRACT A series of single-phase rare earth-doped bismuth ferrites were prepared by the solid state reaction method. After characterizing the samples with XRD, the bulk density measurements were carried out by the immersion method. The ultrasonic longitudinal (Vl ) and shear (Vs ) wave velocities were measured using 1 MHz quartz transducers with the help of the pulse transmission technique. Using the ultrasonic velocity values, Young’s and rigidity moduli along with Poisson’s ratio and Debye temperatures were calculated. As the materials are porous, the zero porous moduli have also been calculated using the Hasselman and Fulrath model. The observed variation of elastic moduli with different dopants has been explained qualitatively. The low-temperature behavior of ultrasonic longitudinal (Vl ) wave velocities was also measured. A small change of slope was observed at 208 K in BFO, BLFO and BSFO samples. Finally, the ultrasonic attenuation coefficient values of all the samples were also measured.

Selective Sensing of the Biotinyl Moiety Using Molecularly Imprinted Polyaniline Nanowires

A chemosensor for selective recognition of biotinyl moiety has been devised using electropolymerized film and tested against selective biotinylated targets. The sensor comprises biotin molecularly imprinted polymer (MIP) polymeric nanowires, as a recognition element, overlaid on gold-coated quartz transducers. The preparation of nanostructured MIPs and reference systems have been demonstrated using electrochemical copolymerization of the stabilized complex between the template (biotin), the functional monomer (4-aminobenzoic acid), and cross-linker (aniline) and/or sacrificial biotin-modified Al2O3 membrane. Density functional theoretical studies signify formation of a stable hydrogen-bonded complex of biotin with 4-aminobenzoic acid in the pre-polymerization mixture. Scanning electron microscope studies revealed uniformly grown and densely packed polyaniline hierarchical structures. Piezoelectric microgravimetry under flow injection analysis (FIA) conditions revealed selective binding of biotin methyl ester (BtOMe, 4) (79.89 ± 2.17 Hz/mM) with imprinted polyaniline hierarchical structures over 10 fold higher than the non-imprinted counterpart. The detection limit of the MIP is 50 nM under optimized conditions. Particularly, the sensor selectively recognizes BtOMe from structural or functional analogues, such as thiamine (4.87 ± 0.10 Hz/mM) and pyridoxamine (12.08 ± 0.24 Hz/mM). Importantly, the MIP hierarchical structures were shown to be selective for biotinylated targets (biotin moiety labeled cytochrome C, dextran, oxytocin and obestatin).

Nematic liquid crystal mixtures dedicated to thermally tunable terahertz devices

ABSTRACTLow-loss nematic liquid crystal mixtures with low temperatures of nematic-to-isotropic phase transition are tested at terahertz frequencies. Experimental results show that through control of ambient temperature, the thermally induced transmittance’s tunability of quartz transducers infiltrated with these mixtures can change of up to 4% for 0.9 THz. Thermally tunable devices based on soft matter may find applications in next-generation modulation and switching components operating in the terahertz regime.

Fessenden and Boyle: Two Canadian Sonar Pioneers

Reginald Fessenden developed voice-modulated radio in the early 20th century using special alternators and microphones capable of handling kilowatts of power. When the Titanic struck the iceberg in 1912, Fessenden, then in Boston, developed an audio-frequency acoustic transmitter-receiver, which he used to detect an iceberg at two miles. When the “Great War” began, UK interests turned to detecting submarines. Ernest Rutherford, on behalf of the Bureau of Investigation and Research (BIR), invited former students A. B. Wood, and R. W. Boyle, to join the anti-submarine effort. Fessenden was also consulted. The team detected submarines using Fessenden’s device but experienced difficulty determining target bearing. After consulting Paul Langevin, Boyle agreed that quartz transducers operating at ultrasonic frequencies should provide a solution. Boyle then developed the UK Type 112 “ASDIC” which was being fitted to Royal Navy warships just as the War ended. Boyle returned to the University of Alberta after the war and continued work in ultrasonics. In 1929 he was appointed Director of Physics at Canada’s National Research Council. There he established an Acoustics Section, and during World War II started a scientific activity in Halifax, NS, which later became the Naval Research Establishment.

From Canton to the Curie brothers: The dawn of sonar

Toward the end of the First World War, Paul Langevin and Robert Boyles developed the first underwater echo-ranging systems capable of detecting and localizing submarines, with important consequences for the outcome of the Second World War. Their invention involved the use of quartz transducers for initial generation of sound and reception of the echo, and vacuum tubes for amplification of the (much weakened) received signal. The distance to the object responsible for the echo could be deduced from the two-way travel time and known speed of sound. The advances in scientific knowledge leading to these technologies are traced from the discoveries of the compressibility of water (1762, John Canton), thermionic emission (1853, Edmond Becquerel), and piezoelectricity (1880, Jacques and Pierre Curie).

Physical characteristics on high-pressure combustion and propelling process of bulk-loaded energetic liquid

The objective of this study is to analyze high-pressure combustion characteristics of liquid propellant and projectile motion problem of the bulk-loaded propellant gun (BLPG). The BLPG described utilizes a mixture of hydroxyl ammonium nitrate and hydrocarbon fuel to replace gunpowder typically used in such guns. The motivation for such a development is to discard the need for a shell casing whereby carrying only propellant and bullets will reduce both the mass and volume per shot. The combustion processes of the bulk-loaded energetic liquid propellant are transient and mainly controlled by turbulent mixing of gas–liquid, thus resulting in the instability of interior ballistics of the BLPG. In this work, direct measurements of the pressure variation and projectile velocity with multiple chamber geometries on the combustion process of bulk-loaded liquid propellant are performed using quartz pressure transducer and timing device. The results indicate that better ballistic repeatability is achieved with the stepped-wall structure for the combustion chamber of the BLPG and a useful degree of controlling pressure oscillation is also achieved by this stepped-wall geometry. Moreover, based on this background, the numerical simulation is devoted to a special combustion issue under transient high-pressure and high-temperature condition, namely studying steady combustion mechanism in a stepped-wall combustion chamber with full monopropellant on one end of that is stationary and the other end can move with a high speed. The numerical results present utilizing the stepped-wall geometry in the combustion chamber itself can exert boundary control on combustion evolution during part of the interior ballistic cycle and the steps can induce an increase in the radial turbulent flow components causing a faster burn time to the chamber wall that lead to a reduction in the gas–liquid surface area, which is the postulated source of instabilities that have resulted in pressure variations.

A technique for measuring dynamic friction coefficient under impact loading.

We develop a novel setup based on the split Hopkinson pressure bar technique to test the dynamic friction coefficient under impact loading. In the setup, the major improvement is that the end of the incident bar near the specimen is wedge-shaped, which results in a combined compressive and shear loading applied to the specimen. In fact, the shear loading is caused by the interfacial friction between specimen and bars. Therefore, when the two loading force histories are measured, the friction coefficient histories can be calculated without any assumptions and theoretical derivations. The geometry of the friction pairs is simple, and can be either cuboid or cylindrical. Regarding the measurements, two quartz transducers are used to directly record the force histories, and an optical apparatus is designed to test the interfacial slip movement. By using the setup, the dynamic friction coefficient of PTFE/aluminum 7075 friction pairs was tested. The time resolved dynamic friction coefficient and slip movement histories were achieved. The results show that the friction coefficient changes during the loading process, the average data of the relatively stable flat plateau section of the friction coefficient curves is 0.137, the maximum normal pressure is 52 MPa, the maximum relative slip velocity is 1.5 m/s, and the acceleration is 8400 m(2)/s. Furthermore, the friction test was simulated using an explicit FEM code LS-DYNA. The simulation results showed that the constant pressure and slip velocity can both be obtained with a wide flat plateau incident pulse. For some special friction pairs, normal pressure up to a few hundred MPa, interfacial slip velocities up to 10 m/s, and slip movement up to centimeter-level can be expected.

Characterization of Local Cavity Pressures in Squeeze Casting of Magnesium Alloy AM50

In this study, the experimental measurement of the pressure distribution in a cylindrical die cavity for squeeze casting of magnesium alloy AM50A was carried out. Piezo-electric quartz pressure transducers were integrated into a die cavity for real-time pressure measurements. The experimental results revealed that local cavity pressures at various locations changed with time in the duration of squeeze casting solidification and cooling. The pressure transfer rate varied considerably within the casting geometry. The distribution of local cavity pressures was inhomogeneous in the cavity.

Measurement of gas storage processes in shale and of the molecular diffusion coefficient in kerogen

Total gas storage capacity in many shale gas reservoirs arises from three sources: compressed gas in the micro- and nano-scale pores, adsorbed gas on the inner surfaces of pores in kerogen—the main constituent of organic materials in shale—and dissolved gas molecules in kerogen. The storage capacity of and transport processes for each of these three sources of gas are different, and accordingly, appropriate models and production strategies should be developed on the basis of actual physics. Of great relevance to field development and management is knowing the contribution of each source to daily production and ultimate gas recovery. A valuable body of literature has addressed the first two sources, but the last source has not been studied in detail. We developed a technique to measure the gas capacity from each of the above-mentioned three sources simultaneously, in a small piece of a shale sample, through batch pressure decay experiments. Temporal pressure decay is recorded using a quartz high-resolution pressure transducer for several days. The pressure-decline curve shows distinctive slope changes representing different storage processes. Pressure decline at the earliest time represents gas migration into the micro- and nano-pores. This is followed by a change in the slope of the pressure decline in an intermediate time, representing gas adsorption onto the inner surface of kerogen pores. At the later time, the slope of the pressure decline changes again, representing gas diffusion into kerogen. In the samples we tested, we found that dissolved gas in kerogen can contribute about 22% of the total gas-in-place. Assuming that gas molecules diffuse into the walls of the pores in kerogen, we used a Fickian diffusion model and a parameter-estimation technique to estimate the gas molecular diffusion coefficient in kerogen. We measured the diffusion coefficient of methane in amorphous kerogen as being on the order of 10−20m2/s.

Using Split Hopkinson Pressure Bars to Perform Large Strain Compression Tests on Neoprene at Intermediate and High Strain Rates

The strain rate sensitivity of neoprene is characterized using a modified split Hopkinson pressure bar (SHPB) system at intermediate (50 s-1, 100 s-1) and high (500 s-1, 1000 s-1) strain rates. We used two quartz piezoelectric force transducers that were sandwiched between the specimen and experimental bars respectively to directly measure the weak wave signals. A laser gap gage was employed to monitor the deformation of the sample directly. Three kinds of neoprene rubbers (Shore hardness: SHA60, SHA65, and SHA70) were tested using the modified split Hopkinson pressure bar. Experimental results show that the modified apparatus is effective and reliable for determining the compressive stress-strain responses of neoprene at intermediate and high strain rates.