Parylene is widely used in the field of biomedical engineering due to its strong barrier properties against water and ions, as well as its superior biocompatibility. In this study, we have developed a pressure sensor module specifically for electronic capsules, where parylene is employed as the sealing material. The pressure sensors were packaged using parylene C and parylene N films with thicknesses of 15 μm, 30 μm, 45 μm, 60 μm, and 75 μm. The effect of parylene coating thickness on the performance of pressure sensors was investigated quantitatively by experiments. Various performance indicators such as sensitivity, linearity, root mean square error (RMSE), repeatability and dynamic response of the pressure sensors packaged with different parylene thicknesses have been thoroughly tested and analyzed. This research bears significance in informing the design of implantable pressure sensors.

In recent years, repackaging technology has been widely used in miniaturized implantable pressure sensors. However, the current packaging structure still has significant problems regarding biocompatibility, environmental adaptability, and measurement accuracy, which greatly limits its application in vivo measurement systems. In this paper, we report a method for implantable pressure sensor repackaging based on silicone oil, polydimethylsiloxane (PDMS) film, and polymer (parylene) coating. A systematic investigation using finite element analysis is conducted to assess the impact of packaging components on sensor performance, providing a solid theoretical foundation for packaging optimization. Experimental results demonstrate that when the parylene coating thickness is below 30 µm, the sensors exhibit superior linearity, repeatability, and reliability, along with exceptional stability and dynamic response across clinically relevant pressure ranges. This research provides valuable insights into the packaging design of implantable pressure sensors, facilitating the development of more stable, reliable, and cost-effective sensors for in vivo measurement systems.