Physical effects from etching parameters of the Bragg Grating Waveguide fabricated on porous silicon nanostructure

Multilayer structure of Bragg Grating Waveguide (BGW), porous silicon (PSi)-based was fabricated and characterized. The BGW was directly etched on a PSi-based planar waveguide. Adjustment of parameters for the electrochemical process will let the realization of multilayer properties of PSi. Fabricated BGW structure depends on thickness and layers of porous structure, and also average pore size. It is well known from previous study that the modulation of multilayer PSi much affected by the HF concentration of electrolyte, etching time, and current density applied during the electrochemical etching process. Surface homogeneity and layer uniformity are also the scope of study and both are much relying on those factors. The average refractive index, n and pore sizes for the multilayer structure were determined and the comparison of the results based from the study was shown. Fabricated BGW on PSi is now intensely investigated for application as an optical sensor for chemical substances.