In this study, homoepitaxial SrTiO$_3$ thin films were deposited on SrTiO$_3$ (001) substrates with different energy density at very low oxygen partial pressure by using a pulsed laser deposition (PLD) method. We carried out X-ray diffraction (XRD), atomic force microscopy (AFM), and resistivity measurements to understand the crystallinity, morphology and electrical properties of these epitaxial films. All films showed homogeneous and uniform morphologies with small root mean square (RMS) roughnesses. The films also exhibited metallic behaviors at temperatures from 2 K to 300 K, indicating that our homoepitaxial SrTiO$_3$ thin films were doped because of nonstoichiometric cations or oxygen deficiencies.

Keywords: Titanate, Homoepitaxy, Roughness, Pulsed laser deposition