Comparison of surface morphologies in GaN films grown by rf-MBE and MOCVD on vicinal sapphire (0 0 0 1) substrates

• Published in: Journal of crystal growth 2009-03, Vol.311 (7), p.2049-2053
• Main Authors: Shen, X.Q., Shimizu, M., Okumura, H., Xu, F.J., Shen, B., Zhang, G.Y.
• Format: Article
• Language: English
• Subjects: A1. Surface structure; A3. Metalorganic chemical vapor deposition; A3. Molecular beam epitaxy; B1. Nitride; Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Methods of crystal growth; physics of crystal growth; Methods of deposition of films and coatings; film growth and epitaxy; Molecular, atomic, ion, and chemical beam epitaxy; Physics; Theory and models of crystal growth; physics of crystal growth, crystal morphology and orientation
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2008.12.019

Surface morphologies of GaN films grown on vicinal sapphire (0 0 0 1) substrates by molecular beam epitaxy (MBE) and metalorganic chemical vapor deposition (MOCVD) are investigated using atomic force microscopy (AFM). It is found that surface morphologies of GaN films depend not only on the vicinal angle and the inclination direction of the substrate, but also on the growth technique. However, the phenomenon concerning the surface step bunching during the growth is common and independent of the growth technique. Our experimental results give important hints to the precise control of the surface morphology in order to achieve high-quality device structures.