Piezoelectric mems sensor, such as force, pressure, deformation sensor or microphone, with improved sensitivity

An electronic device, comprising:

• a microprocessor control unit;
• and
• an acoustic transductor coupled to the microprocessor control unit, the acoustic transductor comprising:
• a membrane of semiconductor material having a first surface and a second surface;
• a cavity extending from the first surface of the membrane toward the second surface, wherein a portion of the membrane forms a hinge between a bottom surface of the cavity and the second surface of the membrane;
• and
• a sensitive region on the first surface and covering the cavity, the sensitive region having a first portion fixed to the membrane at a first side of the cavity and a second portion fixed to the membrane at a second side of the cavity.

A method comprising:

• detecting forces or deformations according to a piezoelectric principle, wherein detecting comprises detecting forces acting transversely to a MEMS sensor including:
• a membrane of semiconductor material having a first surface and a second surface;
• a compliant portion within the membrane, the compliant portion extending from the first surface to the second surface of the membrane and separating a first area from a second area of the membrane, the first and second areas arranged on different sides of the compliant portion, the compliant portion having a Young's modulus of elasticity that is lower than a Young's modulus of elasticity of the first and second areas of the membrane;
• and
• a sensitive region comprising piezoelectric material, the sensitive region extending on the first surface and over the compliant portion, the sensitive region having at least one first portion fixed to the first area of the membrane and one second portion fixed to the second area of the membrane, a third area of the membrane arranged between the compliant portion and the second surface and forming a hinge element, wherein the forces act in a direction transverse to the first surface, wherein detecting comprises:
• converting the forces acting in the direction transverse to the first surface into tensile forces acting, respectively, on the first and second portions of the sensitive region in opposite directions;
• and
• measuring, on the sensitive region, an electrical quantity variable with the transverse forces.