A high-temperature piezoelectric material exhibits a good balance between high maximum use temperature and large piezoelectricity. This is achieved by the combination of discovery phase transition in scandium aluminum nitride (ScxAl1 − xN) alloy thin films, dual cosputtering, which leads to nonequilibrium films.

Visualization of stress distribution has been realized by a nondestructive mechanoluminescence (ML) from SrAl2O4:Eu, which can emit three magnitudes higher visible light than that well-known ML substance quartz. A simulation result confirms such image successfully reflects the distribution. kinetic model for SrAl2O4:Eu is proposed.

The idea and successful practice of a stress sensor to sense mechanical by an artificial skin, i.e., self-diagnosis thin film, has been realized, through the fabrication high-luminescence piezoelectric film which can reproducibly emit strong visible light upon stressing. strongest luminescent consists nanosized crystallites ZnS doped with 1.5 at. % Mn, in Mn acts as emitting center. intensity emitted luminescence responds applied directly onto or underlying material reversibly reproducibly,...

The authors have investigated the influence of growth temperature and scandium concentration on piezoelectric response aluminum nitride (ScxAl1−xN) films prepared by dual reactive cosputtering. strongly depends concentration. at 400 °C gradually increases with increasing On other hand, 580 drastically decreases in from 30% to 40%. We think that drastic change is due disordered grain growth.

The ferroelectricity of (Al1−xScx)N (x = 0–0.34) thin films with various thicknesses was investigated. were prepared at 400 °C on (111)Pt/TiOx/SiO2/(001)Si substrates by the radio frequency dual-source reactive magnetron sputtering method using Al and Sc targets under pure N2 gas or a mixture Ar gases. film deposited showed larger remanent polarization than those + mixture. Ferroelectricity observed for x 0.10–0.34 about 140-nm-thick gas. 0.22 down to 48 nm in thickness from...

A highly efficient dye-sensitized solar cell (DSC) was fabricated using a nanocrystalline nitrogen-doped titania electrode. The properties of the powder, film, and were investigated. substitution oxygen sites with nitrogen atoms in structure confirmed by X-ray photoemission spectroscopy (XPS). UV−vis spectrum powder film showed visible light absorption wavelength range from 400 to 535 nm. An enhancement incident photon-to-current conversion efficiency (IPCE) 380−520 nm 550−750 observed. 8%...

Abstract A sintered sensor element based on WO3 was found to be very sensitive NO and NO2. The sensitivity, defined as the ratio of resistance in gases that air, high 31 97 200 ppm 80 NO2, respectively, at 300 °C. well suited for sensing low levels. Satisfactory performances NO2 were exhibited regions 0–800 0–200 ppm, respectively.

The effects of the grain size on sensor for were investigated. By hydrolyzing ammonium paratungstate with hot nitric acid in solution and calcining resulting precipitate air at prescribed temperatures range 300 to 600°C, mean crystallite sizes varied 16 57 nm. sensitivities elements (10 ppm) as well (200 remained independent down , below which increased steeply a decrease reaching sensitivity values three four times large those .

We report the realization of dynamic image stress distribution by developing a remarkably strong mechanoluminescence (ML) material Sr0.975Al2O3.985:Eu0.01, which can emit four orders magnitude larger intensity than that reported ML quartz crystal. This be mixed in target composite or coated on surface to sense emitting visible light. method is applicable visualization solid not only atmosphere but also an aqueous environment.

The authors have investigated the influence of scandium concentration on power generation figure merit (FOM) aluminum nitride (ScxAl1−xN) films prepared by cosputtering. FOM strongly depends concentration. Sc0.41Al0.59N film was 67 GPa, indicating that is five times larger than AlN. higher those lead zirconate titanate and Pb(Mg1/3Nb2/3)O3-PbTiO3 films, which highest reported for any piezoelectric thin films. high due to d31 low relative permittivity.

We have investigated the high sensitive piezoelectric response of c-axis oriented aluminum nitride (AlN) thin films prepared on polyethylene terephthalate (PET) films. The AlN were deposited using a radio frequency magnetron sputtering method at temperatures close to room temperature. c axes perpendicularly PET film surfaces. sensor consisting and is flexible like electrical charge linearly proportional stress within wide range from 0to8.5MPa. can respond frequencies 0.3 over 100Hz measures...

This paper reports the piezoelectric properties of ScAlN thin films. We evaluated coefficients d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">33</sub> and xmlns:xlink="http://www.w3.org/1999/xlink">31</sub> Sc xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> Al xmlns:xlink="http://www.w3.org/1999/xlink">1-x</sub> N films directly deposited onto silicon wafers, as well radio frequency (RF) electrical characteristics...

The aim of this study is to obtain a systematic insight into the scandium (Sc) concentration dependence spontaneous polarization (Psp) in ScxAl1−xN by using first-principles calculations. From calculated results, we observe that structural change from c-axis polarized wurtzite structure nonpolarized layered hexagonal takes place at x = 0.67, and decreases nonlinearly with Sc concentration. Furthermore, calculate polarizations each cation individually find aluminum–nitrogen (Al–N) (PspAlN)...

The temperature dependence of ferroelectric properties was investigated for (Al0.8Sc0.2)N films 9–130 nm thick prepared on (111)Pt/TiOx/SiO2/Si substrates. coercive fields (Ec) these decreased with increasing measurement up to 523 K, irrespective film thickness, thus realizing polarization switching because the applicable maximum electric field is beyond Ec. As a resultant, remanent (Pr) above 100 μC cm−2 ascertained 9 at 373 and 423 which more than 5 times larger those HfO2-based same...

The triboluminescence intensity from stress-activated Sr3Al2O6:Eu,Dy (SAO-ED) was so strong that we could see it with the naked eye in atmosphere. luminescence integrated about five hundred times as high of crystal sugar. We think light emission is due to movement dislocations and 4f7–4f65d transition doped Eu2+ ions analysis emitted light. Furthermore, have discovered new phenomenon SAO-ED recovered by irradiation ultraviolet

BaMgSiO 4 (BMS) can be sensed to blue light (wavelength λ=405 nm) by doped europium (Eu). Eu BMS turns bright pink, and is bleached green (λ=475–532 irradiation in several seconds. The coloration-decoloration process repeatable first. colored state hardly changes for over 480 h (20 days), stable even at 100 °C. blue-green photochromism explained electron transfers between oxygen defects. broadens the absorption band of BMS, supplies excited electrons. defects form traps, which catch...

Aluminum nitride (AlN) is one of piezoelectric materials, which are eagerly anticipated for use in microelectromechanical systems (MEMS) applications such as communication resonators, sensors, and energy harvesters. AlN particularly excellent generated voltage characteristics the MEMS rather than oxide materials lead zirconium titanate Pb(Zr, Ti)O3. However, it necessary to improve properties order advance performance MEMS. We dramatically increased coefficient d33 films by simultaneously...

The effect of pure mechanical strain on ferroelectricity was investigated for (001)-one-axis-oriented (Al0.8Sc0.2)N films deposited (111)Pt-coated substrates with different thermal expansion coefficients. lattice strains were successfully controlled by using coefficients, though the composition is same. changes in remanent polarization (Pr) and coercive field (Ec) values these can be understood internal parameter u representing crystal anisotropy a wurtzite structure. These results suggest...