Rational Design of Capacitive Pressure Sensors Based on Pyramidal Microstructures for Specialized Monitoring of Biosignals

TLDR

Demand for specialized pressure sensors has grown, and while capacitive sensors are versatile, a tunable and predictable design requires a new fabrication method. The authors present an improved fabrication method that uses a pyramid microstructured dielectric layer with a lamination layer to produce tunable, consistent, and reproducible pressure sensors. The method combines pyramid microstructured dielectrics and lamination, and a simple predictive model is developed to forecast sensor performance across material and geometric parameters. The fabricated sensors match predicted trends, the model is experimentally validated, and the approach enables targeted design of a pressure sensor for in‑vitro pulse sensing.

Abstract

Abstract There is an increasing demand for specialized pressure sensors in various applications. Previously, capacitive pressure sensors have been shown to have wide versatility in use, with a high degree of potential tuning possible through manipulating the geometry or material selection of the dielectric layer. However, in order to make sensors that are tunable and predictable, the design and fabrication method first needs to be developed. Presented here is an improved fabrication method to achieve tunable, consistent, and reproducible pressure sensors by using a pyramid microstructured dielectric layer along with a lamination layer. The as‐produced sensor performance is able to match predicted trends. Further, a simple model based on this system is developed and its efficacy is experimentally confirmed. Then, the model to predict a wide range of material and microstructure geometric properties prior to device fabrication is used to provide trends on sensor performance. Finally, it is demonstrated that the new method can be used to targetedly design a pressure sensor for a specific application—in vitro pulse sensing.