In this work, porous silicon (P-Si) structures were fabricated by anodizing n-type monocrystalline Si into an ethanoic-HF solution. Anisotropic electrochemical etching with constant time and current density was carried out to fabricate pores and their average diameter was found to be ~700 nm. Raman spectra exhibited widened peaks for red, blue, and green wavelengths. The widened photoluminescence (PL) spectrum was blue-shifted owing to the quantum confinement effect. The P-Si exhibited an energy gap of 1.80 eV and manifested a direct bandgap. The photoresponse of the fabricated P-Si based device was studied at different laser irradiation wavelengths in the range of 400-1100 nm. The best photoresponse was observed for 785 nm wavelength and the corresponding sensitivity was determined to be 9.4%. Hence, the P-Si can potentially be used for visible range photodetectors.

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