VISIBLE ELECTROLUMINESCENCE FROM EU-CAF2 LAYERS GROWN BY MOLECULAR-BEAM EPITAXY ON P-SI(100)

Visible electroluminescence (EL) is observed at room temperature by cu rrent injection into Eu:CaF2 layers containing 7.5 and 8.0 at. % Eu gr own by molecular beam epitaxy on lightly doped (100) p-type silicon. T he EL spectra are broad with peaks near 700 and 600 nm. respectively, Room temperature photoluminescence spectra for the same samples exhibi ted peaks near 420 nm, with higher doped samples showing a more pronou nced long wavelength tail, Although both metal and indium-tin-oxide (I TO) contacts were successfully used for current injection, the best EL intensity stability was achieved with contacts made of a 100 Angstrom thick Al layer covered by a 2500 Angstrom thick ITO layer. (C) 1997 A merican Institute of Physics. [S0003-6951(97)01951-7].