Temperature-insensitive fiber pressure sensor based on fabry-pérot interferometry

This paper presents the fiber pressure sensor with temperature-insensitive based on the principle of Fabry-Pérot interferometry. The design and fabrication of the sensor are based on MEMS technique and only needs a few of simple procedures. The pressure sensing membrane consists of a base polyimide layer, a metal reflective layer, and a SU-8 layer covered on the metal layer. Also, the fiber end facet is coated another SU-8 layer for temperature compensation. The analysis on the thicknesses of temperature compensator and pressure membrane is analyzed by FEM model. This pressure sensor exhibits an approximately linear response to applied pressure ranging from 0 to 60 kPa under the temperature difference about 100°C The simple fabrication, small size, linear response, and temperature-insensitive make the sensor suitable for many industrial applications.