An aerosol deposition based MEMS piezoelectric accelerometer for low noise measurement

Abstract

Potentially applied in low-noise applications such as structural health monitoring (SHM), a 1-axis piezoelectric MEMS accelerometer based on aerosol deposition is designed, fabricated, simulated, and measured in this study. It is a cantilever beam structure with a tip proof mass and PZT sensing layer. To figure out whether the design is suitable for SHM, working bandwidth and noise level are obtained via simulation. For the first time, we use aerosol deposition method to deposit thick PZT film during the fabrication process to achieve high sensitivity. In performance measurement, we obtain the charge sensitivity, natural frequency, working bandwidth and noise equivalent acceleration of 22.74 pC/g, 867.4 Hz, 10–200 Hz (within ±5% deviation) and 5.6 $$\mu {{{\rm{g}}}}/\sqrt{{{{\rm{Hz}}}}}$$ μ g / Hz (at 20 Hz). To demonstrate its feasibility for real applications, vibrations of a fan are measured by our designed sensor and a commercial piezoelectric accelerometer, and the results match well with each other. Moreover, shaker vibration measurement with ADXL1001 indicates that the fabricated sensor has a much lower noise level. In the end, we show that our designed accelerometer has good performance compared to piezoelectric MEMS accelerometers in relevant studies and great potential for low-noise applications compared to low-noise capacitive MEMS accelerometers.

Polymeric piezoelectric accelerometers with high sensitivity, broad bandwidth, and low noise density for organic electronics and wearable microsystems

“…The average thermoelectrical noise density is computed as 1.39 µg/ , with a standard deviation of 3.7%. The new design exhibits an average in-band noise density of 1.40 µg/ , with a standard deviation of 3.63%, featuring a thermoelectrical noise that is ten times greater; these results are in agreement with findings from existing studies 16 , 33 on the dominance of the thermoelectrical noise in piezoelectric accelerometers. Furthermore, the noise from the readout circuit, utilizing the AD8608 operational amplifier with a noise density of 8 nV/ 48 , corresponds to a 0.27 µg/ distortion in the in-band noise density, as per the experimental results.…”

“…Our previous PVDF-based accelerometer had a sensitivity of 21.82 pC/g. Although this flat-band sensitivity was comparable to those of several recent PZT-based accelerometers 15 , 16 , our previous polymeric piezoelectric accelerometers only have a limited bandwidth of 58.5 Hz.…”

“…To implement these practical applications, critical research in the next phase is developing a proper packaging method. As noted by Gong et al 16 , piezoelectric accelerometers do not need vacuum sealing, which is the basis of simple packaging processes based on 3D-printed polymer components. Recently, Liu et al experimentally demonstrated the feasibility of using a 3D-printed package to monolithically integrate a MEMS accelerometer and a force sensor 49 .…”

A High-Sensitivity MEMS Accelerometer Using a Sc0.8Al0.2N-Based Four Beam Structure

“…Presently, there is a growing demand for MEMS accelerometers with small sizes, high sensitivity, and superior stability [ 17 ]. MEMS accelerometers can be classified based on their principles of operation, including capacitive [ 9 , 18 ], piezoresistive, resonant [ 19 , 20 ], and piezoelectric types [ 21 , 22 , 23 , 24 ]. Piezoelectric MEMS accelerometers exhibit several advantages over other types, including a wider operating frequency range, along with low power consumption, low-temperature dependence, and high sensitivity [ 25 , 26 ].…”

Electric-Force Conversion Performance of Si-Based LiNbO3 Devices Based on Four Cantilever Beams

“…The piezoelectric cantilever beams are critical in designing intelligent systems [1][2][3] as the primary structure of sensors. The cantilever beam structures [4], characterized by wide operating bandwidth, lightweight, powerful driving force, and high electromechanical conversion efficiency, have been used in the fields of micrometer/nanomechanical systems [5][6][7], server hard disk failure detection [8,9] and controller model validation [10,11]. Therefore, the modeling analysis and dynamic motion behavior of piezoelectric cantilever beams have attracted significant works in the literature [12,13].…”