Catalyst and its diameter dependent growth kinetics of CVD grown GaN nanowires

Journal Article · Sun Apr 15 04:00:00 EDT 2012 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2012.01.012· OSTI ID:22212487

Samanta, Chandan ^[1]; Chander, D. Sathish ^[1]; Ramkumar, J. ^[2]

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1. Department of Physics, Indian Institute of Technology Kanpur (India)
2. Department of Mechanical Engineering, Indian Institute of Technology Kanpur (India)

Graphical abstract: GaN nanowires with controlled diameter and aspect ratio has been grown using a simple CVD technique. The growth kinetics of CVD grown nanowires investigated in detail for different catalysts and their diameters. A critical diameter important to distinguish the growth regimes has been discussed in detail. The results are important which demonstrates the growth of diameter and aspect ratio controlled GaN nanowires and also understand their growth kinetics. Highlights: Black-Right-Pointing-Pointer Controlled diameter and aspect ratio of GaN nanowires achieved in simple CVD reactor. Black-Right-Pointing-Pointer Nanowire growth kinetics for different catalyst and its diameters were understood. Black-Right-Pointing-Pointer Adatoms vapor pressure inside reactor plays a crucial role in growth kinetics. Black-Right-Pointing-Pointer Diffusion along nanowire sidewalls dominate for gold and nickel catalysts. Black-Right-Pointing-Pointer Gibbs-Thomson effect dominates for palladium catalyst. -- Abstract: GaN nanowires were grown using chemical vapor deposition with controlled aspect ratio. The catalyst and catalyst-diameter dependent growth kinetics is investigated in detail. We first discuss gold catalyst diameter dependent growth kinetics and subsequently compare with nickel and palladium catalyst. For different diameters of gold catalyst there was hardly any variation in the length of the nanowires but for other catalysts with different diameter a strong length variation of the nanowires was observed. We calculated the critical diameter dependence on adatoms pressure inside the reactor and inside the catalytic particle. This gives an increasing trend in critical diameter as per the order gold, nickel and palladium for the current set of experimental conditions. Based on the critical diameter, with gold and nickel catalyst the nanowire growth was understood to be governed by limited surface diffusion of adatoms and by Gibbs-Thomson effect for the palladium catalyst.

• OSTI ID: 22212487
• Journal Information: Materials Research Bulletin, Journal Name: Materials Research Bulletin Journal Issue: 4 Vol. 47; ISSN MRBUAC; ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
77 NANOSCIENCE AND NANOTECHNOLOGY
ASPECT RATIO
CATALYSTS
CHEMICAL VAPOR DEPOSITION
ELECTRON MICROSCOPY
GALLIUM NITRIDES
GOLD
NICKEL
PALLADIUM
QUANTUM WIRES
VAPOR PRESSURE