Analytical Study of Highly Sensitive Mems Based Bragg Grating Pressure Sensor

Abstract

A model of MEMS based Bragg Grating Pressure Sensor is analytically proposed in this paper. In MEMS pressure sensor, the shift of wavelength of only one Bragg grating incorporated into a waveguide gives an erroneous outcome because of the cross sensitivity rendered by different parameters including temperature. In this design, the sensor consisting of dual identical Waveguide Bragg Gratings (WBGs) integrated in a curved waveguide in silicon micro-machined circular diaphragm is presented. The pitch of the Bragg gratings changes upon the application of pressure on the diaphragm, and hence, the corresponding wavelength is shifted. As the wavelength shifts because of the temperature, in the two identical waveguide gratings in equal amount, the error occurs due to the change of temperature can be eliminated. So, the Pressure Sensitivity (PS) can be measured correctly. A parametric analysis of this proposed sensor is performed utilizing MATLAB 2015a programming. Pressure sensitivities are found to be 2.0 and 1.8 picometre per Pascal for the two Bragg gratings.