Oxygen Incorporation in the Molecular Beam Epitaxy Growth of ScxGa1−xN and ScxAl1−xN

• Published in: physica status solidi (b) 2020-04, Vol.257 (4), p.n/a
• Main Authors: Casamento, Joseph, Xing, Huili Grace, Jena, Debdeep
• Format: Article
• Language: English
• Subjects: nitrides; oxygen; piezoelectrics; scandium; thin films
• ISSN: 0370-1972; 1521-3951
• DOI: 10.1002/pssb.201900612

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–Al2O3 template substrates with Sc contents up to 26 at%, the oxygen concentration is found to be between 1019 and 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. Secondary‐ion mass spectrometry (SIMS) is used to determine impurity concentrations of carbon and oxygen in two scandium‐containing nitride semiconductor multilayer thin‐film heterostructures: ScxGa1−xN/GaN (x = 0–0.28) and ScxAl1−xN/AlN (x = 0–0.26) grown by molecular beam epitaxy (MBE). In the ScxGa1−xN–GaN and ScxAl1−xN–AlN heterostructures, oxygen concentration is found to be below 1 × 1019 cm−3 and from 1 × 1019 to 1 × 1021 cm−3, respectively.