FERROELECTRICS IN PLANAR GEOMETRY: FABRICATION AND PERSPECTIVES FOR INTEGRATION

ABSTRACT

Single crystalline ultrathin films of (Ba,Sr)TiO₃ (BST) and BiFeO₃ (BFO) on MgO (001) substrate were fabricated by RF sputtering at high oxygen pressure, electric filed in planar geometry was applied by interdigital electrode system. Based on the obtained materials switchable ferroelectric and multiferroic nanostructures were fabricated by focused ion beam milling.

The structure, dielectric, linear-optical and nonlinear (electro)optical properties of the films of different thicknesses in wide range of frequencies of applied voltage were studied. High efficiency of planar ferroelectric switching is shown. Nanostructuring allows to change dielectric and optical properties of ferroelectric materials and increase in this way the range of switchability of functional parameters.

Fabricated structures with high switchability efficiency and low dielectric losses are very promising for fabrication of electro-optical modulators; small size combined with high switching contrast provides conditions for efficient integration in planer geometry.

Keywords:

• ferroelectrics
• thin films
• in-plane switching
• electro-optical
• properties
• nanostructures