Structural and optical characterizations of Er:Y2O3 thin films deposited by pulsed laser deposition (PLD) from metal targets have been undertaken. The back-round gas during deposition plays an important role on the crystalline quality of the film. It was found that mixture of oxygen and an inert gas is needed in order to stabilize the Y2O3 phase. Emission spectroscopy of the plasma during deposition reveals that the oxidation of yttrium atoms during gas-phase transport is not necessary in this particular case. Using the pressure-distance scaling law, high quality films can be obtained on sapphire (0 0 0 1) under a wide range of pressures. The 0.69 mum thick films, deposited under an O-2/Ar atmosphere of 6/244 mTorr and substrate-target distance of 45 mm, exhibit high levels of fluorescence and efficient guiding effects along the entire length of planar waveguide samples. (C) 2002 Elsevier Science B.V. All rights reserved.