The growth of thin films of LiNbO3 and Er:LiNbO3 on LiNbO3 single crystals produced by pulsed laser deposition (PLD) was studied. Samples were characterized by RBS/Channeling Spectrometry, X-ray diffraction measurements, Secondary Ion Mass Spectroscopy (SIMS) and photoluminescence (PL) measurements. Film preparation is performed in a two-step process including deposition and in-situ-annealing. Buried Er doped layers of approx. 800 nm thickness were grown.