Structural and optical properties of hexagonal and orthorhombic YMnO₃ thin films prepared by metal-organic decomposition method

Abstract Hexagonal and orthorhombic YMnO 3 thin films were prepared by the metal-organic decomposition method, on (111) oriented yttria-stabilized zirconia (YSZ) and off-axis SrTiO 3 (001) substrates, respectively. Hexagonal YMnO 3 thin film on a YSZ (111) substrate exhibits high crystallinity with (000 l ) orientation and in-plane epitaxial relationships of YSZ [11 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover accent="true"> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> <mml:mo>̅</mml:mo> </mml:mover> </mml:math> ]//hexagonal YMnO 3 [10 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover accent="true"> <mml:mrow> <mml:mn>1</mml:mn> </mml:mrow> <mml:mo>̅</mml:mo> </mml:mover> </mml:math> 0]. Spectroscopic ellipsometry shows that the optical constants of the hexagonal YMnO 3 thin film are in good agreement with those of the bulk samples. On the other hand, orthorhombic YMnO 3 thin film on the off-axis SrTiO 3 (001) substrate was oriented in (00 l ) and exhibited SrTiO 3 [110]//orthorhombic YMnO 3 [100] and SrTiO 3 [110]//orthorhombic YMnO 3 [010] epitaxial relationships from the twinned structure with lattice distortion.