Sputtered films of Er3+-doped gallium lanthanum sulfide glass

Thin films of Er3+-doped gallium lanthanum sulfide (GLS) glass were prepared by RF magnetron sputtering onto fused silica and BK7 glass substrates. The films were characterized by use of SEM imaging, X-ray diffractometry, and energy dispersive spectroscopy. They are shown to be glassy, uniform in composition, and to exhibit an RMS surface roughness of < 8 Å. The fluorescence lifetimes of the 4I11 / 2 → 4I13 / 2 and 4I13 / 2 → 4I15 / 2 transitions of Er3+ were measured at each processing stage.