Multi-parameter coupling molecular dynamics investigation of crystal growth and defect formation in InxGa1-xN Films

YS Wu and X Gong and CP Chen and JH Li, MATERIALS TODAY COMMUNICATIONS, 49, 114420 (2025).

DOI: 10.1016/j.mtcomm.2025.114420

The epitaxial growth of InGaN films on heterogeneous substrates often introduces severe defects due to lattice and thermal mismatches. In this work, molecular dynamics simulations are conducted to examine the coupled effects of substrate polarity, temperature, atomic incidence angle, and In composition on InGaN deposition on GaN substrates. Results show that elevated substrate temperatures enhance atomic mobility and promote diffusion toward energetically favorable lattice sites. This facilitates atomic diffusion toward energetically favorable lattice sites, resulting in the formation of ordered GaN and InN crystals. Films grown on (0001) Gaterminated surfaces exhibit superior morphology and structural integrity. A critical incidence angle (45 degrees) is identified, below which crystal quality is improved with limited morphological variation. The In composition ratio (x) strongly affects structural evolution and induces a non-monotonic trend in dislocation density. The study integrates four innovations: a unified multi- parameter coupling analysis, identification of a critical incidence angle, quantitative correlation between In composition and defect microstructure, and cross-scale relevance to Molecular Beam Epitaxy (MBE) cavity design. These findings guide high-quality InGaN epitaxy and MBE equipment optimization.

Return to Publications page