Defect structures in (001) zincblende GaN/3CSiC nucleation layers

Vacek, Petr and Frentrup, Martin and Lee, Lok Yi and Massabuau, Fabien C.-P. and Kappers, Menno J. and Wallis, David J. and Groger, Roman and Oliver, Rachel A. (2021) Defect structures in (001) zincblende GaN/3CSiC nucleation layers. Journal of Applied Physics, 129 (15). 155306. ISSN 0021-8979

[thumbnail of Vacek-etal-jap2021-defect-structures-in-zincblende-nucleation-layers]
Preview
Text. Filename: Vacek_etal_jap2021_defect_structures_in_zincblende_nucleation_layers.pdf
Accepted Author Manuscript

Download (1MB)| Preview

    Abstract

    The defect structure of zincblende GaN nucleation layers grown by metalorganic vapor-phase epitaxy on 3C-SiC/Si (001) was investigated by high-resolution scanning transmission electron microscopy. Perfect dislocations, partial dislocations, and stacking faults are present in the layers. Perfect dislocations are identified as 60° mixed-type and act as misfit dislocations to relieve the compressive lattice mismatch strain in GaN. Stacking faults are mainly bounded by 30° Shockley partial dislocations and rarely by Lomer–Cottrell partial dislocations, both of which are able to relieve the compressive lattice mismatch strain in the layer. We propose that the stacking faults and their partial dislocations originate from the dissociation of perfect dislocations present in the zincblende GaN layer and by direct nucleation of partial dislocations loops from the surface. These are the two main mechanisms that lead to the final defect structure of the zincblende GaN nucleation layers.

    ORCID iDs

    Vacek, Petr, Frentrup, Martin, Lee, Lok Yi, Massabuau, Fabien C.-P. ORCID logoORCID: https://orcid.org/0000-0003-1008-1652, Kappers, Menno J., Wallis, David J., Groger, Roman and Oliver, Rachel A.;