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arXiv · 1912.04495

Oxygen Incorporation in the MBE growth of ScxGa1-xN and ScxAl1-xN

Joseph Casamento·Huili Grace Xing·Debdeep Jena
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Abstract

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 atomic percent, the oxygen concentration is found to be below 1x1019/cm3, 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 atomic percent, the oxygen concentration is found to be between 1019 to 1021/cm3, again directly correlated with the Sc content. The increased oxygen and carbon arises during the deposition of scandium alloyed layers.

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Joseph Casamento, Huili Grace Xing, Debdeep Jena. 2019-12-10. Oxygen Incorporation in the MBE growth of ScxGa1-xN and ScxAl1-xN. https://doi.org/10.1002/pssb.201900612

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