Luminescent films of porous silicon were obtained by laser ablation of crystalline silicon. The spectral and temporal characteristics of light emission from laser ablated porous silicon (LAPS) films critically depend on the chemical composition of the atmosphere in which they were fabricated. Luminescent characteristics, spatial structure, and chemical composition of LAPS were compared with the properties of porous silicon obtained by a standard electrochemical method on the same silicon substrate. ©1996 American Institute of Physics.