Abstract
Germanium-based oxides such as rutile GeO2 are garnering attention owing to their wide band gaps and the prospects of ambipolar doping for application in high-power devices. Here, we present the use of germanium tetraisopropoxide (GTIP), a metal-organic chemical precursor, as a source of germanium for the demonstration of hybrid molecular beam epitaxy for germanium-containing compounds. We use Sn1-xGexO2 and SrSn1-xGexO3 as model systems to demonstrate our synthesis method. A combination of high-resolution X-ray diffraction, scanning transmission electron microscopy, and X-ray photoelectron spectroscopy confirms the successful growth of epitaxial rutile Sn1-xGexO2 on TiO2(001) substrates up to x = 0.54 and coherent perovskite SrSn1-xGexO3 on GdScO3(110) substrates up to x = 0.16. Characterization and first-principles calculations corroborate that germanium occupies the tin site, as opposed to the strontium site. These findings confirm the viability of the GTIP precursor for the growth of germanium-containing oxides by hybrid molecular beam epitaxy, thus providing a promising route to high-quality perovskite germanate films.
| Original language | English (US) |
|---|---|
| Article number | 69 |
| Journal | Communications Materials |
| Volume | 3 |
| Issue number | 1 |
| DOIs | |
| State | Published - Dec 2022 |
| Externally published | Yes |
Bibliographical note
Funding Information:MBE growth of stannate (F.L., T.K.T., and B.J.) were supported by the U.S. Department of Energy through DE-SC002021. Germanate growth and characterization (F.L. and D.L.) were supported by the Air Force Office of Scientific Research (AFOSR) through Grants FA9550-21-1-0025 and FA9550-21-0460 and in part through NSF DMR-1741801. Parts of this work were carried out in the Characterization Facility, University of Minnesota, which receives partial support from the NSF through the MRSEC (Award Number DMR-2011401) and the NNCI (Award Number ECCS-2025124) programs. B.E.M., S.R.S., and S.A.C. carried out the STEM and XPS analysis with support from the U.S. Department of Energy, Office of Science, Division of Materials Sciences and Engineering under Award #10122 to Pacific Northwest National Laboratory (PNNL). PNNL is a multiprogram national laboratory operated for the U.S. Department of Energy (DOE) by Battelle Memorial Institute under Contract No. DE-AC05-76RL0-1830. STEM sample preparation was performed at the Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by the DOE’s Biological and Environmental Research program and located at PNNL. STEM imaging was performed in the Radiological Microscopy Suite (RMS), located in the Radiochemical Processing Laboratory (RPL) at PNNL.
Funding Information:
MBE growth of stannate (F.L., T.K.T., and B.J.) were supported by the U.S. Department of Energy through DE-SC002021. Germanate growth and characterization (F.L. and D.L.) were supported by the Air Force Office of Scientific Research (AFOSR) through Grants FA9550-21-1-0025 and FA9550-21-0460 and in part through NSF DMR-1741801. Parts of this work were carried out in the Characterization Facility, University of Minnesota, which receives partial support from the NSF through the MRSEC (Award Number DMR-2011401) and the NNCI (Award Number ECCS-2025124) programs. B.E.M., S.R.S., and S.A.C. carried out the STEM and XPS analysis with support from the U.S. Department of Energy, Office of Science, Division of Materials Sciences and Engineering under Award #10122 to Pacific Northwest National Laboratory (PNNL). PNNL is a multiprogram national laboratory operated for the U.S. Department of Energy (DOE) by Battelle Memorial Institute under Contract No. DE-AC05-76RL0-1830. STEM sample preparation was performed at the Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by the DOE’s Biological and Environmental Research program and located at PNNL. STEM imaging was performed in the Radiological Microscopy Suite (RMS), located in the Radiochemical Processing Laboratory (RPL) at PNNL.
Publisher Copyright:
© 2022, The Author(s).