The influence of growth temperatures on the characteristics of GaN nanowires

• Published in: Applied surface science 2011-10, Vol.258 (1), p.542-546
• Main Authors: Low, L.L., Yam, F.K., Beh, K.P., Hassan, Z.
• Format: Article
• Language: English
• Subjects: Chemical vapour deposition; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Diffraction; Emission; Exact sciences and technology; Gallium nitrides; GaN; Growth temperature; Nanowires; Optimization; Photoluminescence; Physics; Spectral emissivity; Vapour–liquid–solid
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2011.08.071

► Synthesis of GaN nanowires at various growth temperatures, i.e. 750 °C, 850 °C, 900 °C, 950 °C, and 1000 °C. ► Study the effect of growth temperatures on the morphological, structural and optical characteristics of GaN nanowires. ► Study the presence of phonon replicas in the blue emission of photoluminescence spectra of synthesized GaN nanowires. This paper presents the investigation of the properties of GaN nanowires synthesized from Ni-catalyzed chemical vapour deposition method under various growth temperatures. The influence of the growth temperatures on the morphological, structural and optical characteristics of the synthesized GaN nanowires was investigated in this work. Field-emission scanning electron microscopy images revealed that the 950 °C was the optimal growth temperature for synthesizing uniform, straight and smooth morphology of GaN nanowires. X-ray diffraction results demonstrated that the synthesized low dimensional GaN structures have the hexagonal wurtzite structure. Ultraviolet and blue emissions were detected from photoluminescence measurements. In addition, phonon replicas with the energy separation of 90 meV have been observed at the lower energy of the blue emission region in photoluminescence spectra.