Erbium-doped silicon has been prepared using Ultra High Vacuum/Chemical Vapor Deposition (UHV/CVD). An erbium mctalorganic compound, tris-1,1,1,5,5,5-hexafluoro-2,4-pentanedionato erbium (111) (Er(HFAC)3), was used as the erbium source and silane was used as the silicon source. Films were deposited at 650 °C at a total pressure of 1 mtorr. Erbium concentrations between 8×1019 and 1×1018 Er atoms/cm3 were prepared by varying the Er source reservoir temperature. Low temperature photoluminescence measurements showed strong emission at 1.54μm. The films are single crystal, but with a high concentration of threading defects.