Development and Characterization of ZnO Piezoelectric Thin Film Sensors on GH4169 Superalloy Steel Substrate by Magnetron Sputtering

Abstract

At present, piezoelectric sensors are primarily applied in health monitoring areas. They may fall off owing to the adhesive’s durability, and even damage the monitored equipment. In this paper, a piezoelectric film sensor (PFS) based on a positive piezoelectric effect (PPE) is presented and a ZnO film is deposited on a GH4169 superalloy steel (GSS) substrate using magnetron sputtering. The microstructure and micrograph of ZnO piezoelectric thin films were analyzed by an X-ray diffractometer (XRD), energy dispersive spectrometer (EDS), scanning electron microscope (SEM), and atomic force microscope (AFM). The results showed that the surface morphology was dense and uniform and had a good c-axis-preferred orientation. According to the test results of five piezoelectric sensors, the average value of the longitudinal piezoelectric coefficient was 1.36 pC/N, and the average value of the static calibration sensitivity was 19.77 mV/N. We selected the sensor whose parameters are closest to the average value for the dynamic test experiment and we drew the output voltage response curve of the piezoelectric film sensor under different loads. The measurement error was 4.03% when repeating the experiment six times. The research achievements reveal the excellent performance of the piezoelectric film sensor directly deposited on a GH4169 superalloy steel substrate. This method can reduce measurement error caused by the adhesive and reduce the risk of falling off caused by the aging of the adhesive, which provides a basis for the research of smart bolts and guarantees a better application in structural health monitoring (SHM).

Self‐Powered Rapid Response Flexible Pressure Sensor for Wearable Application

“…ZnO has a Zn 2+ ‐terminated, O 2− ‐terminated polar structure in which Zn atoms are arranged in the hexagonal closest stacking with four oxygen atoms around each Zn atom and further form a [ZnO 4 ] 6 tetrahedral coordination structure with one top angle of the tetrahedra pointing in the negative direction of the c ‐axis. As the XRD plots in Figure 1q show, under the predetermined process conditions, [ 40 ] all the prepared films showed intense ZnO(002) diffraction peaks at 2 θ of 34.17°, which were close to the standard card of PDF#36‐1451, indicating a good c‐axis orientation. A schematic of the ZnO crystal model is shown in Figure 1r.…”

“…The crosslinked conductive films not only need to have good conductivity without deformation but also need to have high conductivity and ductility while being well bonded to the substrate in various significant deformation situations. NiCr [40,41] is often used as a conductive electrode for flexible devices because of its chemical stability, good ductility, and electrical conductivity. After consideration, NiCr was used as the crosslinked conductive film.…”

Research on bolt looseness monitoring based on electromechanical impedance transmissibility technology

“…The smart bolt used in this experiment is a double-layer piezoelectric layer structure that can enhance the piezoelectric performance of piezoelectric thin film sensors [43]. This method can reduce the measurement error caused by an adhesive, reduce the risk of falling off caused by adhesive aging, and ensure a better application in SHM [44]. Our laboratory has conducted SEM, EDS, and XRD characterization of ALN, NiSi, and SiO 2 thin films, and the results showed that the prepared thin films meet the preparation requirements of piezoelectric thin film sensors.…”

Structural Characterization of ZnO Thin Films Deposited onto Silicon Substrates using Cathodic Magnetron Sputtering

“…In addition to its use in solar cells, zinc oxide has excellent piezoelectric properties and has been widely studied for use in piezoelectric sensors, nanogenerators, accelerometers, and pressure sensors. It can be deposited onto substrates using methods such as chemical vapor deposition, pulsed laser deposition, sol-gel treatment, and magnetron sputtering [4].…”