Microcrystalline and porous on microcrystalline silicon thin films were produced. The photoluminescence characteristics of porous on microcrystalline silicon were studied and compared with those from microcrystalline and porous silicon grown on silicon wafers. Under steady state it is possible to excite these samples with visible light at room temperature. This excitation gives rise to a red photoluminescence band, which is similar to that of porous silicon excited under the same conditions. MicroRaman and transmission spectroscopy shows that the porous silicon layer was produced below the microcrystalline silicon thin film that acts as a shield for excitation and emission of radiation with a wavelength smaller than 500 nm. Sample thickness, crystallite size and crystalline fraction are determined. The results are discussed in terms of the theoretical framework based in the fluctuating quantum wire model for porous silicon.