Pulsed Laser Deposition for Complex Oxide Thin Film and Nanostructure

Structure Quality of LuFeO3 Epitaxial Layers Grown by Pulsed-Laser Deposition on Sapphire/Pt

“…A similar procedure was applied for the other samples Pt10, Pt20, and Pt30. 10 20 Figure 2. X-ray reflectivity curves taken during pulsed-laser deposition (PLD) growth: the parameters of the curves are the total numbers of laser shots of the LFO deposition.…”

“…The epitaxial orientation is determined by the minimum free energy, which is related to the bonding across the substrate-epilayer interface and to the mismatch of the substrate and layer lattices. It is recognized that, despite the triangular symmetry matching on the abovementioned substrates, there is no obvious lattice match between h-RFeO 3 and Al 2 O 3 (0001) (a = 4.7602 Å), yttrium-stabilized zirconia (YSZ) (111) (a = 7.30 Å), or Pt (111) (a = 5.548 Å) [10].Nevertheless, an epitaxial growth of h-LuFeO 3 (LFO) could be obtained using the pulsed-laser deposition [6][7][8][9]11]. This means that the azimuthal epitaxial orientation of h-LuFeO 3 films cannot be explained simply by the lattice mismatch.…”

“…This approach reveals how the structural setup of the layer/substrate interface would affect the structure and the morphology of the deposited h-LuFeO 3 .Epitaxial strain is an extremely important issue in epitaxial thin film growth because the strain may change the properties of the epilayer, offering opportunities of material engineering; see the reviews in References [12,13], among others. For the Al 2 O 3 (0001) substrates, the lattice mismatch of the supercell is small but the huge misfit of the lattice constant suggests weak interfacial bonding [10]. The growth of an additional Pt interlayer aims on the one side to reduce the lattice mismatch between the deposited h-LuFeO 3 layer and Al 2 O 3 (0001) substrate and on the other side to develop ferroelectric and multiferroic devices, since the Pt layer may act as the bottom electrode.There is a considerable scientific and technological interest in the growth of epitaxial thin Pt metal film on dielectric insulators substrates like MgO (100) [14], SrTiO 3 [15], Al 2 O 3 (0001) [16], and ZrO 2 [17] by various deposition methods such as PLD [14,17], magnetron sputtering [16], and molecular-beam epitaxy (MBE) [18] due to the high conductivity and oxygen stability of Pt [15].…”

“…The epitaxial orientation is determined by the minimum free energy, which is related to the bonding across the substrate-epilayer interface and to the mismatch of the substrate and layer lattices. It is recognized that, despite the triangular symmetry matching on the abovementioned substrates, there is no obvious lattice match between h-RFeO 3 and Al 2 O 3 (0001) (a = 4.7602 Å), yttrium-stabilized zirconia (YSZ) (111) (a = 7.30 Å), or Pt (111) (a = 5.548 Å) [10].…”

“…Epitaxial strain is an extremely important issue in epitaxial thin film growth because the strain may change the properties of the epilayer, offering opportunities of material engineering; see the reviews in References [12,13], among others. For the Al 2 O 3 (0001) substrates, the lattice mismatch of the supercell is small but the huge misfit of the lattice constant suggests weak interfacial bonding [10]. The growth of an additional Pt interlayer aims on the one side to reduce the lattice mismatch between the deposited h-LuFeO 3 layer and Al 2 O 3 (0001) substrate and on the other side to develop ferroelectric and multiferroic devices, since the Pt layer may act as the bottom electrode.…”