A micro-fabricated force sensor using an all thin film piezoelectric active sensor.

Area of Science:

• Biomedical Engineering
• Materials Science
• Sensor Technology

Background:

• Accurate pressure and force measurement are critical in biomedical fields, including minimally invasive surgery and cancer cyst detection via palpation.
• Existing sensing technologies may have limitations in sensitivity or require external power sources.

Purpose of the Study:

• To design and fabricate a thin-film piezoelectric force sensor capable of measuring both shear and normal forces.
• To develop an enhanced sensing tool for analyzing gentle touches without external voltage sources.
• To evaluate the sensor's performance and feasibility for biomedical applications.

Main Methods:

• Fabrication of a thin-film piezoelectric force sensor integrating an arrayed piezoelectric sensor layer with a precut glass top plate.
• Utilizing four stress-concentrating legs to connect the components.
• Testing the sensor's response to varying pressures (3 kPa to 30 kPa) and directional movements.

Main Results:

• The fabricated sensor demonstrated linear response within the 3 kPa to 30 kPa pressure range.
• The sensor accurately detected signal responses corresponding to the direction of movement.
• The proposed design eliminates the need for an external voltage source, unlike Field-Effect Transistor (FET) sensors.

Conclusions:

• The developed thin-film miniaturized piezoelectric force sensor shows strong feasibility for biomedical applications.
• The sensor's ability to measure both shear and normal forces with high sensitivity makes it suitable for delicate procedures.
• This technology offers a promising advancement for non-invasive diagnostic tools and surgical instruments.