Pressure Sensor Based on Polyvinylidene Fluoride Nanofibers Directly Written upon Silicon Substrate

Abstract

A novel integration of silicon substrate and near-field electrospun polyvinylidene fluoride (PVDF) nanofibers is applied to pressure sensor for dynamic pressure measurement. PVDF is the widely known polymer with outstanding piezoelectric property, and has a wide range of applications in energy, biology, and sensors. Near field electrospinning (NFES) has obvious advantages in the preparation of direct written PVDF nanofibers with high piezoelectric performance. This paper mainly presents the preparation of pressure sensor of PVDF nanofibers on silicon substrate with integrated subtractive and additive manufacturing methods. First, a silicon substrate with diaphragm was fabricated with MEMS techniques. Then, aligned parallel PVDF nanofibers were deposited on the diaphragm with NFES as sensing element. Last, a home-made dynamic pressure testing device was used for testing the properties, and its results showed that: with the increase of pressure, the output signal was gradually enhanced, and the sensitivity of the prototype sensor was finally obtained, which is 2214.4mV/MPa (the circuit amplification factor of 20,000 times), and the optimal linearity is 2.8%.