The use of anodic oxidation as a post-treatment of porous silicon has been investigated to enhance the external quantum efficiency of electroluminescence from a device based on a thin transparent indium tin oxide contact on porosifiedn+-type silicon. Enhancement in external quantum efficiency of three orders of magnitude has been obtained. We report here an external quantum efficiency of 0.21&percent;. The treatment also greatly improves the stability of the device. Results can be explained by the fact that anodic oxidation considerably reduces leakage current flowing via nonconfined silicon. ©1998 American Institute of Physics.