西岡 洋

350-nm-thick BiFeO3(BFO) thin films have been deposited by dual ion beam sputtering on SrRuO3-buffered SrTiO3(001) substrates of 0° and 0.5° off-cut along [100] at various Bi2O3-side/Fe2O3-side beam current ratio. The BFO thin film on 0.5° off-cut STO substrate deposited at beam current ratio of 20 mA/30 mA show fully saturated D-E hysteresis loops at room temperature. The remanent polarization (2Pr) was 132 μC/cm2. Stripe domain structure was also observed in IP piezoelectric response image. It is considered that the improvement of leakage of BFO on 0.5° off-cut STO substrate is due to reduction of 109° domain walls. © 2011 IEEE.

Epitaxially a- and b-axis-oriented (Bi 3.25Nd 0.75) Ti 3O 12 (BNT-0.75) films and nanoplates have been fabricated on four Nb:TiO 2(101) substrates with 0-0.79 mass% Nb by high-temperature sputtering. It is shown from piezoresponse scanning force microscopy (PFM) measurements that the effective piezoelectric coefficients (d 33) at room temperature derived from the two linear gradients for the asymmetric displacement-voltage hysteresis loop are 11-13 pm/V. © 2011 IEEE.