Thin films of amorphous Ga2S3 and rare-earth sulphides

Abstract The aim of this research is to prepare amorphous thin films of undoped gallium sulphide and doped with rare-earth sulphides, of rare-earth sulphides and to investigate their physical properties. We have prepared thin amorphous films of Ga 2 S 3 , EuS, Er 2 S 3 , Gd 2 S 3 , and Ga 2 S 3 doped with rare-earth sulphides (Ga 2 S 3 :EuS, Ga 2 S 3 :Er 2 S 3 , Ga 2 S 3 :Gd 2 S 3 ) by Pulsed Laser Deposition (PLD). The corresponding targets for preparation of amorphous thin films were obtained by Spark Plasma Sintering (SPS) from commercially available powders of binary sulphides. The structural results for the undoped and doped Ga 2 S 3 thin films indicate a packing of disordered layers similar to that of amorphous As 2 S 3 . Femtosecond laser irradiation of the Ga 2 S 3 thin films shows a photoexpansion effect at low laser power (85–100 mW) and an ablation effect at higher laser power (above 105 mW). The threshold between low power and high power pulses is situated at higher value for Ga 2 S 3 (100 mW) in comparison with the case of As 2 S 3 thin films (20 mW).