Ferroelectric field effect transistor based on BaSnO₃

In order to integrate the newly discovered high-mobility perovskite semiconductor BaSnO3 [1] with a ferroelectric perovskite, we have grown epitaxial ferroelectric Pb(Zr,Ti)O3 (PZT) on 4 % La-doped BaSnO3 (BLSO) and SrRuO3 (SRO) electrodes by pulsed laser deposition technique. X-ray diffraction measurement confirms that the PZT films were epitaxially grown and shows that the lattice constants of PZT depend on the Zr/(Zr+Ti) ratio in PZT. An all-epitaxial sandwich PZT ferroelectric capacitor structure was fabricated with BLSO and SRO electrodes, and the strain effect on the ferroelectric properties of PZT was investigated. The polarization-electric field (P-E) hysteresis curve is discussed from the viewpoint of the strain effect. Furthermore, a ferroelectric field effect transistor with a BaSnO3 channel layer was successfully fabricated, and carrier modulation of BaSnO3 by the ferroelectric polarization field was observed. The output characteristics, transfer characteristics and breakdown field of the ferroelectric transistor will be presented.

[1] H. J. Kim, U. Kim et al., Appl. Phys. Express 5, 061102 (2012).