Crystalline MgO(111) has the potential to be an effective template for the heteroepitaxial integration of BTO(111) and other functional oxides on 6H-SiC (0001). Deposition of MgO on 6H-SiC (0001) at 140 °C resulted in a twinned structure with only (111) orientation. By heating the MgO(111) after deposition to 650 °C at a background pressure of 1.0× 10-9 Torr or depositing the MgO at 650 °C, the twinned structure can be minimized, resulting in a reflection high energy electron diffraction (RHEED) pattern characteristic of random epitaxial islands. The use of a 2 nm MgO(111) template layer proved optimal for deposition of crystalline BTO(111) by molecular beam epitaxy on 6H-SiC (0001). The BTO was found to be twinned with a 60° in-plane rotation. The grain formation of the BTO resulted in a transmission dominated RHEED pattern. Deposition of BTO at a higher substrate temperature resulted in large grain formation, 50 nm in size, but an increased surface roughness of 1.4±0.1 nm over a 1 μm 2 area. In order to integrate BTO in a multiferroic device with multilayers of BTO(111) and hexagonal ferrites, it will be necessary to optimize the processing conditions to establish a smoother BTO surface for the subsequent heteroepitaxy of the magnetic film.
|Original language||English (US)|
|Number of pages||5|
|Journal||Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures|
|State||Published - 2008|
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Electrical and Electronic Engineering