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Title: Germanium dioxide: A new rutile substrate for epitaxial film growth
Rutile compounds have exotic functional properties that can be applied for various electronic applications; however, the limited availability of epitaxial substrates has restricted the study of rutile thin films to a limited range of lattice parameters. Here, rutile GeO 2 is demonstrated as a new rutile substrate with lattice parameters of [Formula: see text] and [Formula: see text]. Rutile GeO 2 single crystals up to 4 mm in size are grown by the flux method. X-ray diffraction reveals high crystallinity with a rocking curve having a full width half-maximum of 0.0572°. After mechanical polishing, a surface roughness of less than 0.1 nm was obtained, and reflection high-energy electron diffraction shows a crystalline surface. Finally, epitaxial growth of (110)-oriented TiO 2 thin films on GeO 2 substrates was demonstrated using molecular beam epitaxy. Templated by rutile GeO 2 substrates, our findings open the possibility of stabilizing new rutile thin films and strain states for the tuning of physical properties.  more » « less
Award ID(s):
1719875 2039380
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Vacuum Science & Technology A
Page Range / eLocation ID:
Medium: X
Sponsoring Org:
National Science Foundation
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