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Secondary‐ion mass spectrometry (SIMS) is used to determine impurity concentrations of carbon and oxygen in two scandium‐containing nitride semiconductor multilayer heterostructures: ScxGa1−xN/GaN and ScxAl1−xN/AlN grown by molecular beam epitaxy (MBE). In the ScxGa1−xN/GaN heterostructure grown in metal‐rich conditions on GaN–SiC template substrates with Sc contents up to 28 at%, the oxygen concentration is found to be below 1 × 1019 cm−3, with an increase directly correlated with the scandium content. In the ScxAl1−xN–AlN heterostructure grown in nitrogen‐rich conditions on AlN–Al2O3template substrates with Sc contents up to 26 at%, the oxygen concentration is found to be between 1019and 1021 cm−3, again directly correlated with the Sc content. The increase in oxygen and carbon takes place during the deposition of scandium‐alloyed layers.
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This content will become publicly available on October 14, 2025
Thermoelectric properties of YbZn 11−x Al x
The first investigation on the properties of intermetallic YbZn11for active cooling: an unconventional thermoelectric application.
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- Award ID(s):
- 2230352
- PAR ID:
- 10556109
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Materials Advances
- Volume:
- 5
- Issue:
- 20
- ISSN:
- 2633-5409
- Page Range / eLocation ID:
- 8053 to 8059
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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