Highly Sensitive Porous Silicon Membrane Waveguide Sensor Using Ultra-High Order Mode

This work proposes a label-free porous silicon membrane waveguide biosensor with very high sensitivity due to the utilization of an ultra-high order mode for sensing. Its sensitivity toward refractive index perturbation is simulated and shown to be superior to that of a porous silicon membrane waveguide utilizing a low order mode. The proposed sensor structure is especially suitable for biosensing applications due to its large surface area, oscillating wave interaction with biomolecules, free-space coupling for ease of sensor array integration, and horizontal pore orientation compatible with microfluidics.