Er3+-doped Al2O3 thin films byplasma-enhanced chemical vapor deposition (PECVD) exhibiting a 55-nmoptical bandwidth

We report the first deposition of Er³⁺-doped aluminum oxide thin-film optical waveguides by plasma-enhanced chemical vapor deposition (PECVD). The aluminum and erbium precursors used for the deposition of the thin films were trimethyl-aluminum and Er tri-chelate of 2,2,6,6-tetramethylheptane-3,5 dione respectively. The samples show broad, room-temperature photoluminescence at λ=1.533 μm. The Er³⁺ concentration ranged from 0.01-0.2 at%. The full width half maximum (FWHM) of the Er³⁺ emission spectrum is 55 nm, considerably broader than in silica glass. The radiative lifetime has been measured at 50-mW pump power