Color-sensitivity of Si photodiodes was achieved by integrating porous silicon (PS) Bragg reflectors and Fabry-Perot filters. The PS was formed in the p(+)-type part of the p(+)n junction which required illumination of the samples during anodization. The optimal illumination power density turned out to be a compromise : high power densities are necessary to enable high anodization current densities, but this results in a degraded filter performance. The PS layers had no significant influence on the electrical characteristics of the photodiodes, but as expected they strongly modified the spectral response. The results are in good agreement with the reflectance spectra of the filters.