Secondary‐ion mass spectrometry (SIMS) is used to determine impurity concentrations of carbon and oxygen in two scandium‐containing nitride semiconductor multilayer heterostructures: Sc
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The first investigation on the properties of intermetallic YbZn11for active cooling: an unconventional thermoelectric application.
more » « less- 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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x Ga1−x N/GaN and Scx Al1−x N/AlN grown by molecular beam epitaxy (MBE). In the Scx Ga1−x N/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 Scx Al1−x N–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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Abstract The highest ambient‐pressure Tc among binary compounds is 40 K (MgB2). Higher Tc is achieved in high‐pressure hydrides or multielement cuprates. Alternatively, are explored superconducting properties of binary, metastable sub‐oxides, that may emerge under extremely low oxygen partial pressure. The emphasis is on the rock‐salt structure, which is known to promote superconductivity, and exploring AlO, ScO, TiO, and NbO. Dynamic lattice stability is achieved by introducing metal and oxygen vacancies in the fashion of Nb1−
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