Highly Sensitive Parylene C-Based Flexible Pressure Sensors for Wearable Systems.

Area of Science:

• Materials Science
• Sensor Technology
• Biomedical Engineering

Background:

• Flexible piezoelectric sensors are crucial for wearable technology.
• Parylene C's potential in piezoelectric sensors remains largely unexplored.
• Parylene C offers excellent electrical insulation, chemical inertness, flexibility, and biocompatibility.

Purpose of the Study:

• To investigate Parylene C as a piezoelectric layer for flexible pressure sensors.
• To fabricate and characterize pressure sensors using varying Parylene C film thicknesses.
• To explore the application of these sensors in smart wearable devices.

Main Methods:

• Fabrication of piezoelectric pressure sensors using Parylene C as the active layer between copper electrodes.
• Encapsulation of the sensor with polyimide.
• Preparation of Parylene C films with thicknesses of 10, 25, and 45 μm.
• Characterization of sensor performance, including pressure and frequency sensitivity.

Main Results:

• The fabricated sensors exhibited high sensitivities (pressure: 87.62 mV/kPa, frequency: 580.95 mV/Hz).
• Increasing Parylene C thickness led to a significant increase in output voltage (approx. 300% at 9 Hz).
• Improved piezoelectric coefficients (d33) were observed with increased thickness.

Conclusions:

• Parylene C is a promising material for developing high-performance flexible piezoelectric pressure sensors.
• The study presents a flexible, biocompatible Parylene C-based sensor array suitable for smart gloves.
• This research advances the use of Parylene C in wearable sensing for human-machine interfaces and healthcare.