Room‐temperature electroluminescence at 1.54 &mgr;m is demonstrated in erbium‐implanted oxygen‐doped silicon (27 at. % O), due to intra‐4ftransitions of the Er3+. The luminescence is electrically stimulated by biasing metal‐(Si:O, Er)‐p+silicon diodes. The 30‐nm‐thick Si:O, Er films are amorphous layers deposited onto silicon substrates by chemical‐vapor deposition of SiH4and N2O, doped by ion implantation with Er to a concentration up to ≊1.5 at. %, and annealed in a rapid thermal annealing furnace. The most intense electroluminescence is obtained in samples annealed at 400 °C in reverse bias under breakdown conditions and it is attributed to impact excitation of erbium by hot carriers injected from the Si into the Si:O, Er layer. The electrical characteristics of the diode are studied in detail and related to the electroluminescence characteristics. A lower limit for the impact excitation cross section of ≊6×10−16cm2is obtained. ©1995 American Institute of Physics.