The invention provides a multilayer piezoelectric thin film
cantilever beam sensor and a preparation method therefor. A sacrificial layer releasing process is adopted to release the sacrificial layer from the front surface to form a piezoelectric micro-
cantilever beam structure; the commonly-adopted
CMOS process is fully utilized, so that the process is simple and controllable; the compatibility between the
piezoelectric cantilever beam sensor manufacturing process and an
silicon integrated circuit process is improved; the problem of
pollution existing in a process that the bulk-
silicon substrate is etched by a wet
etching method and the
cantilever beam is released from the back surface is avoided; in addition, the multilayer piezoelectric thin film and a flexible supporting layer are adopted, so that the sensitivity of the sensor or the deformation amplitude of an
actuator is improved, and the response of the cantilever beam to external excitation and the
signal output are improved; in addition, due to the flexible supporting layer, the structure and the
processing technology of the sensor are simplified; and the piezoelectric micro-sensor adopting the structure can be applied to objects of any sizes and any surface shapes, so that the application range of the micro-sensor is expanded.