Step pinning and hillock formation in (Al,Ga)N films on native AlN substrates

• Published in: Journal of applied physics Vol. 132; no. 22
• Main Authors: Schulz, T., Yoo, S.-H., Lymperakis, L., Richter, C., Zatterin, E., Lachowski, A., Hartmann, C., Foronda, H. M., Brandl, C., Lugauer, H. J., Hoffmann, M. P., Albrecht, M.
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 14.12.2022
• Subjects: Adatoms; Aluminum gallium nitrides; Aluminum nitride; Applied physics; Density functional theory; Destabilization; Diffusion length; Epitaxial growth; Mathematical analysis; Nucleation; Pinning; Segments; Substrates; Surface diffusion; Threading dislocations

The influence of edge-type threading dislocations (TDs) on the epitaxial growth of AlGaN on native AlN substrates was investigated theoretically and experimentally. In the step flow growth regime, we find that pure edge-type TDs cause a pinning of surface steps, resulting in curved step segments. Th...