A study of the effect of time of ethanol immersion and passive etching in
the preparation of porous silicon on the photoluminescence (PL) of the material
was carried out. The sample showed a blue shift as well as an enhanced PL
intensity dependent on the time of immersion and passive etching. Also, the
effect of aging on the samples up to 3-months was investigated, which shows a
further blue shift as well as an order of magnitude increase in the intensity.