Growth of Bi2Se3 and Bi2Te3 on amorphous fused silica by MBE

Topological insulator (TI) thin films of Bi2Se3 and Bi2Te3 have
been successfully grown on amorphous fused silica (vitreous
SiO2) substrates by molecular beam epitaxy. We find that such
growth is possible and investigations by X-ray diffraction reveal
good crystalline quality with a high degree of order along the caxis.
Atomic force microscopy, electron backscatter diffraction
and X-ray reflectivity are used to study the surface morphology
and structural film parameters. Angle-resolved photoemission
spectroscopy studies confirm the existence of a topological surface
state. This work shows that TI films can be grown on
amorphous substrates, while maintaining the topological surface
state despite the lack of in-plane rotational order of the
domains. The growth on fused silica presents a promising route
to detailed thermoelectric measurements of TI films, free from
unwanted thermal, electrical, and piezoelectric influences from
the substrate.