Improvement of morphology, structure, and optical properties of GaAs nanowires grown on Si substrates

Conference item

We investigate vertical and defect-free growth of GaAs nanowires on Si (111) substrates via a vapor-liquid-solid (VLS) growth mechanism with Au catalysts by metal-organic chemical vapor deposition (MOCVD). By using annealed thin GaAs buffer layers on the surface of Si substrates, most nanowires are grown on the substrates straight, following (111) direction; by using two temperature growth, the nanowires were grown free from structural defects, such as twin defects and stacking faults. Systematic experiments about buffer layers indicate that V/III ratio of precursor and growth temperature can affect the morphology and quality of the buffer layers. Especially, heterostructural buffer layers grown with different V/III ratios and temperatures and in-situ post-annealing step are very helpful to grow well arranged, vertical GaAs nanowires on Si substrates. The initial nanowires having some structural defects can be defect-free by two-temperature growth mode with improved optical property, which shows us positive possibility for optoelectronic device application. ©2010 IEEE.

Authors: Kang, J; Gao, Q; Joyce, H; Tan, H; Jagadish, C

• Host title: 2010 10th IEEE Conference on Nanotechnology, NANO 2010
• Pages: 470-473
• Publication date: 2010-01-01
• DOI: 10.1109/NANO.2010.5697783
• ISBN: 9781424470334
• Keywords: Nanowire; MOCVD; Si substrate; Epitaxial growth; Defect-free; GaAs