Ultrasonic Microspectroscopy of ZnO Single Crystals Grown by the Hydrothermal Method

Measurementthe act of measuring physical properties that we performhas the potential to contribute to the successful advancement of sciences and society. To open doors in physics and other sciences, various measurement methods and related applications have been developed, and ultrasound has remained a useful probe, power source, and interesting measurement object for the past two centuries. In this paper, we first summarize the basic principles of ultrasound from the viewpoint of measurement techniques for readers who just have started studying or are interested in the field of ultrasonic electronics. Moreover, we also introduce recent studiesultrasonic properties of materials, measurement techniques, piezoelectric devices, nonlinear acoustics, biomedical ultrasound, and ocean acousticsand their trends related to measurement techniques in ultrasonic electronics to provide some ideas for related applications.

Section: Transmittermentioning

confidence: 99%

“…For example, piezoelectric thin films are used for microspectroscopy with high precision and as filters of very high frequencies. 214,215,218,305) Piezoelectric transducers are also used for microfluidic control, 306) in which acoustic streaming in a small area can be controlled by acoustic transducers.…”

Section: Theorymentioning

confidence: 99%

Introduction of measurement techniques in ultrasonic electronics: Basic principles and recent trends

Mizutani¹,

Wakatsuki²,

Ebihara³

2016

“…In the conversion losses, the effect of the propagation loss in the silica glass substrate was subtracted using =f 2 ¼ 9:55 Â 10 À16 dBÁs 2 /m for a longitudinal wave or =f 2 ¼ 1:99 Â 10 À15 dBÁs 2 /m for a shear wave. 21,22) We compared this experimental conversion loss with the theoretical conversion losses of a single layer transducer and a multilayer transducer. Theoretical curves were calculated using a modified Mason's equivalent circuit model including the effect of c-axis tilt angle and electrodes.…”

Section: Transducer Characterizationmentioning

confidence: 99%

Wideband Multimode Transducer Consisting of c-Axis Tilted ZnO/c-Axis Normal ZnO Multilayer

Takayanagi

Yanagitani

Matsukawa

2012

Wideband ultrasonic transducers are required for acoustic imaging and nondestructive evaluation. In this study, we have fabricated transducer consisting of c-axis tilted ZnO/c-axis normal ZnO multilayer on the Au(111)/Ti/silica glass substrate. We have investigated the crystalline orientations and frequency characteristics of the multilayer transducer. An X-ray diffraction analysis and a scanning electron microscopy analysis of the transducer revealed that the c-axis normal ZnO layer was grown on the Au(111) layer during the initial stage of ZnO layer deposition. As ZnO grain growth proceeded, c-axis normal growth change to the c-axis tilted ZnO layer growth. This multilayer transducer excited secondovertone modes of longitudinal and shear waves as well as the fundamental mode in the UHF range. Therefore, the frequency bandwidth of the multilayer transducer was broader than that of a single layer transducer consisting of a c-axis tilted ZnO layer.

“…where h is the frequency of ultrasound, and c cm (= 1440 m/s) and c s (= 6375 m/s) 21) are the velocities of sound in the coupling medium and in the lens substrate, respectively. The diffraction efficiency of a multiple phase levels lens is given by…”

Section: Realization Of Fresnel Lensesmentioning

confidence: 99%

Design and Fabrication of Fresnel Lens and ZnO Thin-Film Transducer

Pan

Bui

Nien

et al. 2011

A four-level Fresnel lens and piezoelectric transducer were fabricated as an ejector using focused ultrasonic energy. The influence of the fabrication parameters on the profile of the focusing lens was investigated. Highly c-axis (002)-oriented ZnO films were successfully deposited on Pt (annealed)/Ti/SiO2/Si substrates under reasonable conditions, such as RF power of 178 W, substrate temperature of 380 °C, deposition pressure of 10 mTorr, and Ar:O2 gas flow ratio of 50%. These conditions were applied and confirmed through investigating the influence of deposition parameters on the properties of ZnO films.