Fabrication and characterization of high-temperature AlN thick-film piezoelectric accelerometer

Piezoelectric thick-film (10-100 mu m) sensors are mainly manufactured using lead zirconate titanate (PZT) materials, however, their performance is limited in high-temperature environments. Therefore, this paper proposes a high-temperature aluminum nitride (AlN) thick-film accelerometer. The AlN film with a thickness of 10 mu m was directly deposited on the stainless steel substrate using the reactive RF magnetron sputtering technique. Compared with the silicon-based piezoelectric accelerometer, the preparation method can improve the energy transfer efficiency of the piezoelectric layer and the fracture toughness of the cantilever beam under vibration deformation and eliminate the need for complicated photolithography, etching, and thinning while being compatible with microelectromechanical systems (MEMS) technology. The experimental results indicated that the sensitivity, resonant frequency, resolution, and thermal noise (T = 300 K) of the accelerometer were 6.73 mV/g, 1193 Hz, 0.45 mg, and 39.76 nV/ root, respectively. Further, the designed accelerometer had long-term Hz Hz (6 h) and stable sensitivity at a temperature of 600 degrees C, indicating its broad potential for application in high- temperature environments.