Structure and ferroelectric properties of $Bi_2VO_{5.5}$ thin films by laser deposition

c-axis oriented thin films of $Bi_2VO_{5.5}$ (BVO), an n=1 member of the Aurivillius family, have been grown on $SrTiO_3$(STO) by pulsed laser deposition. Metallic $LaNiO_3$(LNO) films have been grown on STO and $SiO_2/Si(100)$ substrates; c-axis oriented BVO have been deposited on the lattice matched LNO/STO and $LNO/SiO_2/Si$ where the LNO film acts as an electrode. Trilayer structures, Au/BVO/LNO/STO, LNO/BVO/LNO/STO and Au/BVO/LNO/$SiO_2$/Si have been fabricated and ferroelectric properties of BVO have been confirmed from hysteresis loop measurements. The remnant polarization and coercive field are about $4×10^{-8} C/cm2$ and 25 kV/cm respectively. The dielectric constant of the film was comparable to that of bulk BV