Porous Silicon Optical Distributed Bragg Reflector Sensor: Methods of Characterization

The reflectivity of the porous silicon distributed Bragg reflector optical sensor was calculated by a matrix method for different values of porosity layers. Methods of characterization of reflectance spectra based on analyzing of dominant interference peak as Bragg peak and whole spectrum were considered. Parameters of Bragg peak as the position of peak maxima and FWHM were determined for different ratios/differences of low and high values of refractive indexes of layers. Parameters as dominant wavelength, excitation purity were determined as sensor response and characteristics of the whole reflectance spectrum contrary to separate Bragg peak. Maximum sensitivity is 615.3 for the proposed characterization method based on the dominant wavelength.