Fabrication and Characterization of Piezoelectric PVDF-TrFE Sensor Fabricated Using Spin Coating Method for Biomedical Device Applications

Minimally Invasive Surgery (MIS) has been considered and received more favor since the last two decades by the physicians and researchers rather than traditional open surgery due to better healing conditions after the surgery, less physical pain, and faster recovery process. There are various types of force/pressure sensor technologies in the market. However, the fittest one is the piezoelectric transduction principle for the MIS’s devices like endoscopic grasper or biomedical insertion catheter. A common design and fabrication technique for these kinds of sensors is using PVDF with its copolymer, TrFE, as a piezoelectric material due to its biocompatibility and ease of implantation. In this study, PVDF-TrFE polymer is deposited between two aluminum electrodes via spin-coating method and gone under different post-fabrication processes in order to examine its piezoelectricity and amount of electroactive $\beta$-phase. These processes investigate the effect of various post thermal annealing temperatures, different number of layers of polymer deposition, and the effect of spin-coating speed. This research clearly presents an effective way to fabricate a PVDF-TrFE based tactile sensor and some enhancement techniques according to the author’s novel experimental design to obtain higher $\beta$-phase and, consequently, piezoelectric constant to get a better sense of touch at the end effector of biomedical devices.