Optical sensing analysis of bilayer porous silicon nanostructure

Abstract

Bilayer porous silicon (PSi) nanostructure is proposed as a biosensor by considering the optical performance. The sensitivity of this bilayer PSi nanostructure with triangular lattice is theoretical calculated based on the rigorous coupled wave analysis theory, wavelength interrogation and orthogonal experimental methods. These results show that the bilayer PSi nanostructure can be used as a biosensor according to its excellent linearity relationship between the red shift and reflective index (from 1.3 to 1.8). The optical characteristic and sensitivity of this PSi nanostructure could be modified by changing its lattice constant and structural parameters. It is very useful for the understanding of the application and design for PSi in the field of biosensor.