Effect of an Al2O3 transition layer on InGaN on ZnO substrates by organometallic vapor-phase epitaxy

• Published in: Journal of crystal growth Vol. 310; no. 23; pp. 4908 - 4912
• Main Authors: LI, Nola, WANG, Shen-Jie, HUANG, Chung-Lung, ZHE CHUAN FENG, VALENCIA, Adriana, NAUSE, Jeff, SUMMERS, Christopher, FERGUSON, Ian
• Format: Conference Proceeding Journal Article
• Language: English
• Published: Amsterdam Elsevier 15.11.2008
• Subjects: Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Growth from vapor; Materials science; Methods of crystal growth; physics of crystal growth; Methods of deposition of films and coatings; film growth and epitaxy; Other materials; Physics; Specific materials; Theory and models of crystal growth; physics of crystal growth, crystal morphology and orientation; Vapor phase epitaxy; growth from vapor phase; B1. Nitrides; Organometallic compounds; Crystal growth from vapors; XRD; Gallium nitride; Thin films; Energy gap; Optical transmission; A3. Organometallic vapor phase; Zinc oxide; Indium nitride; Absorption spectra; Diffusion; Depth profiles; Aluminium oxide; Atomic layer method; Annealing; A1. X-ray diffraction; III-V compound; AES; B2: Semiconducting materials; Vapor phase; MOVPE method; Growth mechanism; B1. ZnO substrate; III-V semiconductors
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2008.07.087

InGaN was grown on bare ZnO as well as Al2O3 deposited ZnO substrates by organometallic vapor-phase epitaxy (OMVPE). The Al2O3 transition layer was grown by atomic layer deposition (ALD) in order to prevent Zn and O diffusion from the ZnO substrate and promote nitride growth. In-situ annealing of the transition layer was first performed right before InGaN growth in the chamber. High-resolution X-ray diffraction (HRXRD) measurements revealed that the thin Al2O3 layer after annealing was an effective transition layer for the InGaN films grown epitaxially on ZnO substrates. Optical transmission (OT) was performed to measure the bandgap energy using Sigmoidal fitting. Auger electron spectroscopy (AES) atomic depth profile shows a decrease in Zn in the InGaN layer. The diffusivity of Zn in the GaN layer grown on the bare ZnO substrate is about 5X10-16 cm2/s. Moreover, (0 0 0 2) InGaN layers were successfully grown on 20 nm Al2O3/ZnO substrates after 10 min annealing in a high-temperature furnace.