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arXiv · 2607.15748

Two-step growth of (In,Ga)N pseudo-substrates on GaN templates by plasma-assisted molecular beam epitaxy

Huaide Zhang·Jingxuan Kang·Aidan F. Campbell·Jonas Lähnemann·Oliver Brandt·Lutz Geelhaar
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Abstract

(In,Ga)N layers are grown by plasma-assisted molecular beam epitaxy on GaN templates. We introduce a two-step protocol that involves switching the growth conditions from initially N-stable to metal-stable. Reflection high-energy electron diffraction as well as scanning electron and atomic force microscopy reveal that the first step results in a rough intermediate surface with open pits, whereas the final surface is smooth. The narrow linewidth of the photoluminescence band indicates an excellent compositional homogeneity of the upper layer. Its in-plane lattice constant is determined to be $\approx$3.26 \AA from X-ray diffraction measurements. This combination of favorable properties makes these layers attractive as pseudo-substrates for the growth of red-emitting (In,Ga)N light-emitting diodes. In particular, the approach presented here does not require any complex external processing and is, thus, scalable and economical.

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Huaide Zhang, Jingxuan Kang, Aidan F. Campbell, Jonas Lähnemann, Oliver Brandt, Lutz Geelhaar. 2026-07-17. Two-step growth of (In,Ga)N pseudo-substrates on GaN templates by plasma-assisted molecular beam epitaxy. https://arxiv.org/abs/2607.15748

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