BiFeO 3 thin films have been deposited on (001) SrTiO 3, (101) DyScO 3, (011) DyScO 3, (0001) AlGaN/GaN, and (0001) 6H-SiC single crystal substrates by reactive molecular beam epitaxy in an adsorption-controlled growth regime. This is achieved by supplying a bismuth over-pressure and utilizing the differential vapor pressures between bismuth oxides and BiFeO3 to control stoichiometry in accordance with thermodynamic calculations. Four-circle x-ray diffraction and transmission electron microscopy reveal phase-pure, epitaxial films with rocking curve full width at half maximum values as narrow as 7.2 arc seconds (0.002002̊). Epitaxial growth of (0001)-oriented BiFeO 3 thin films on (0001) GaN, including AlGaN HEMT structures, and (0001) SiC has been realized using intervening epitaxial (111) SrTiO 3 / (100) TiO 2 buffer layers. The epitaxial BiFeO 3 thin films have 2 in-plane orientations: [112̄0] BiFeO 3 || [112̄0] GaN (SiC) plus a twin variant related by a 180̊ in-plane rotation. This epitaxial integration of the ferroelectric with the highest known polarization, BiFeO 3, with high bandgap semiconductors is an important step toward novel field-effect devices.
|Original language||English (US)|
|Number of pages||6|
|Journal||IEEE transactions on ultrasonics, ferroelectrics, and frequency control|
|State||Published - Aug 2009|
All Science Journal Classification (ASJC) codes
- Acoustics and Ultrasonics
- Electrical and Electronic Engineering