The induction of a graphite-like phase on diamond films by a Fe-coating/post-annealing process to improve their electron field emission properties

Journal Article · Fri Apr 15 04:00:00 EDT 2011 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3569887· OSTI ID:21560182

Huang, Pin-Chang; Shih, Wen-Ching ^[1]; Chen, Huang-Chin; Lin, I-Nan ^[2]

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1. Graduate Institute in Electro-Optical Engineering, Tatung University, Taipei 104, Taiwan (China)
2. Department of Physics, Tamkang University, Tamsui, New-Taipei 251, Taiwan (China)

The electron field emission (EFE) process for diamond films was tremendously enhanced by Fe-coating and post-annealing processes. Microstructural analysis indicates that the mechanism for the improvement in the EFE process is the formation of nanographites with good crystallinity that surround the Fe (or Fe{sub 3}C) nanoclusters. Presumably the nanographites were formed via the reaction of Fe clusters with diamond films, viz. by the dissolution of carbons into Fe (or Fe{sub 3}C) clusters and the reprecipitation of carbon species to the surface of the clusters, a process similar to the growth of carbon nanotubes via Fe clusters as catalyst. Not only is a sufficiently high post-annealing temperature (900 deg. C) required but also a highly active reducing atmosphere (NH{sub 3}) is needed to give a proper microstructure for enhancing the EFE process. The best EFE properties are obtained by post-annealing the Fe-coated diamond films at 900 deg. C in an NH{sub 3} environment for 5 min. The EFE behavior of the films can be turned on at E{sub 0} = 1.9 V/{mu}m, attaining a large EFE current density of 315 {mu}A/cm{sup 2} at an applied field of 8.8 V/{mu}m (extrapolation using the Fowler-Nordheim model leads to J{sub e} = 40.7 mA/cm{sup 2} at a 20 V/{mu}m applied field).

• OSTI ID: 21560182
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 8 Vol. 109; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AMMONIA
ANNEALING
ATOMIC CLUSTERS
CARBIDES
CARBON
CARBON COMPOUNDS
CATALYSTS
CHEMICAL COATING
CHEMICAL VAPOR DEPOSITION
CRYSTAL STRUCTURE
CURRENT DENSITY
DEPOSITION
DIAMONDS
ELECTRON EMISSION
ELEMENTS
EMISSION
EXTRAPOLATION
FIELD EMISSION
FILMS
GRAPHITE
HEAT TREATMENTS
HYDRIDES
HYDROGEN COMPOUNDS
IRON
IRON CARBIDES
IRON COMPOUNDS
MATHEMATICAL SOLUTIONS
METALS
MICROSTRUCTURE
MINERALS
MOLECULAR CLUSTERS
NANOSTRUCTURES
NANOTUBES
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
NONMETALS
NUMERICAL SOLUTION
PRECIPITATION
SEPARATION PROCESSES
SURFACE COATING
THIN FILMS
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS