Design of novel thin-film piezoelectric accelerometer

A Simple Analytical Model for MEMS Cantilever Beam Piezoelectric Accelerometer and High Sensitivity Design for SHM (structural health monitoring) Applications

“…Piezoelectric accelerometers have many desirable features, such as extremely low power consumption, high sensitivity, inherent temperature stability, compatibility with the CMOS (complementary metal-oxide semiconductor) manufacturing process [8][9][10], high Q in the range of 80 to 100, high output impedance, and wide operating temperature range (up to 300℃) [8,11,12]. The design and fabrication of micromachined piezoelectric accelerometers have been reported widely [7][8][9][10][11][12][13][14]. Such an accelerometer will record translational and rotational inertial accelerations, as well as gravitational acceleration, as long as parts of these acceleration vectors are in line with the accelerometer's axis of sensitivity.…”

“…The position of the electrical neutral axis, tn1, can be expressed as [37], (9) The lateral strain at any point (x,z) in the beam is in direction at a given (x,z) in the ZnO piezoelectric layer is therefore (12) for 0<x<L. Here, g 31 is the piezoelectric coefficient that can be related to the piezoelectric strain coefficient, d 31 , as (13) where ε r and ε 0 are the dielectric constant of the piezoelectric layer and the permittivity of free space, respectively. By integrating E in (x, z) with respect to z, the induced voltage at any given x is then (14) for 0<x<L. Here,…”

“…The lateral strain at any point (x,z) in the beam is (10) for 0<x<L. The lateral stress in the piezoelectric layer (ZnO) can be written as (11) for 0<x<L. The induced electric field, E in (x,z), in the thickness direction at a given (x,z) in the ZnO piezoelectric layer is therefore (12) for 0<x<L. Here, g 31 is the piezoelectric coefficient that can be related to the piezoelectric strain coefficient, d 31 , as (10) for 0<x<L. The lateral stress in the piezoelectric layer (ZnO) can be written as (11) for 0<x<L. The induced electric field, E in (x,z), in the thickness direction at a given (x,z) in the ZnO piezoelectric layer is therefore (12) for 0<x<L. Here, g 31 is the piezoelectric coefficient that can be related to the piezoelectric strain coefficient, d 31 , as (13) where ε and ε are the dielectric constant of the piezoelectric…”

“…During acceleration, the seismic mass exerts a force on the piezoelectric material resulting in the generation of a charge due to the piezoelectric effect. Piezoelectric accelerometers have many desirable features, such as extremely low power consumption, high sensitivity, inherent temperature stability, compatibility with the CMOS (complementary metal-oxide semiconductor) manufacturing process [8][9][10], high Q in the range of 80 to 100, high output impedance, and wide operating temperature range (up to 300℃) [8,11,12].…”

“…The design and fabrication of micromachined piezoelectric accelerometers have been reported widely [7][8][9][10][11][12][13][14]. Such an accelerometer will record translational and rotational inertial accelerations, as well as gravitational acceleration, as long as parts of these acceleration vectors are in line with the accelerometer's axis of sensitivity.…”