Structural investigation of diamond nanoplatelets grown by microwave plasma-enhanced chemical vapor deposition

2005 ◽  
Vol 20 (3) ◽  
pp. 703-711 ◽  
Author(s):  
Hou-Guang Chen ◽  
Li Chang
Keyword(s):  
Electron Microscopy ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Microwave Plasma ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Plasma Chemical Vapor Deposition ◽  
Transmission Electron ◽  
Side Face ◽  
Face Structure

We report a unique morphology of diamond nanoplatelets synthesized by microwave plasma chemical vapor deposition on Ni coated polycrystalline diamond substrates. The diamond nanoplatelets were as thin as approximately 30 nm. Electron microscopy showed that the diamond nanoplatelets appear in a shape consisting of trapezoid and parallelogram tabular crystallites. Furthermore, the diamond nanoplatelets were single crystalline, as shown by electron diffraction. The edges of nanoplatelets were along the 〈110〉 direction with both the top and bottom tabular surfaces parallel to the {111} plane. Transmission electron microscopy revealed that the twinned planes are parallel to the platelet and side-face structure in ridge shape is bounded by {100} and {111} planes. Lateral growth of diamond nanoplatelet is believed to result from twin and ridge face structure. An oriented thin graphite layer was observed on some diamond nanoplatelets.

Aligned Carbon Nanotubes Via Microwave Plasma Enhanced Chemical Vapor Deposition

1999 ◽  
Vol 593 ◽  
Author(s):  
H. Cui ◽  
D. Palmer ◽  
O. Zhou ◽  
B. R. Stoner
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Microwave Plasma ◽  
Chemical Vapor ◽  
Silicon Substrates ◽  
Multi Wall Carbon Nanotubes ◽  
Field Emission Properties ◽  
Transmission Electron

ABSTRACTAligned multi-wall carbon nanotubes have been grown on silicon substrates by microwave plasma enhanced chemical vapor deposition using methane/ammonia mixtures. The concentration ratio of methane/ammonia in addition to substrate temperature was varied. The morphology, structure and alignment of carbon nanotubes were studied by scanning electron microscopy and transmission electron microscopy. Both concentric hollow and bamboo-type multi-wall carbon nanotubes were observed. Growth rate, size distribution, alignment, morphology, and structure of carbon nanotubes changed with methane/ammonia ratio and growth temperature. Preliminary results on field emission properties are also presented.

scholarly journals Isotope Effect in Thermal Conductivity of Polycrystalline CVD-Diamond: Experiment and Theory

Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 322
Author(s):  
Alexander V. Inyushkin ◽  
Alexander N. Taldenkov ◽  
Victor G. Ralchenko ◽  
Andrey P. Bolshakov ◽  
Alexander V. Khomich
Keyword(s):  
Thermal Conductivity ◽  
Chemical Vapor Deposition ◽  
Isotopic Composition ◽  
Vapor Deposition ◽  
Microwave Plasma ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Cvd Diamond ◽  
Plasma Chemical Vapor Deposition

We measured the thermal conductivity κ(T) of polycrystalline diamond with natural (natC) and isotopically enriched (12C content up to 99.96 at.%) compositions over a broad temperature T range, from 5 to 410 K. The high quality polycrystalline diamond wafers were produced by microwave plasma chemical vapor deposition in CH4-H2 mixtures. The thermal conductivity of 12C diamond along the wafer, as precisely determined using a steady-state longitudinal heat flow method, exceeds much that of the natC sample at T>60 K. The enriched sample demonstrates the value of κ(298K)=25.1±0.5 W cm−1 K−1 that is higher than the ever reported conductivity of natural and synthetic single crystalline diamonds with natural isotopic composition. A phenomenological theoretical model based on the full version of Callaway theory of thermal conductivity is developed which provides a good approximation of the experimental data. The role of different resistive scattering processes, including due to minor isotope 13C atoms, defects, and grain boundaries, is estimated from the data analysis. The model predicts about a 37% increase of thermal conductivity for impurity and dislocation free polycrystalline chemical vapor deposition (CVD)-diamond with the 12C-enriched isotopic composition at room temperature.

CRYSTALLINE CARBON NITRIDE FILMS GROWN BY MICROWAVE PLASMA CHEMICAL VAPOR DEPOSITION

2002 ◽  
Vol 16 (06n07) ◽  
pp. 1091-1095 ◽  
Author(s):  
W. T. ZHENG ◽  
X. WANG ◽  
T. DING ◽  
X. T. LI ◽  
W. D. FEI ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Photoelectron Spectroscopy ◽  
Carbon Nitride ◽  
Microwave Plasma ◽  
Chemical Vapor ◽  
Plasma Chemical ◽  
X Ray ◽  
Plasma Chemical Vapor Deposition

The carbon nitride films were deposited on single crystalline Si(001) and polycrystalline diamond substrates using microwave plasma chemical vapor deposition (MPCVD) with CH4+N2 as well as CH4+NH3 mixtures as the reactive gas source, respectively. Different CH4/N2 and CH4/NH3 gas ratios were tested. The results showed that carbon nitride films with different nitrogen content could more readily be obtained using a mixture of CH4/N2 rather than CH4/NH3. The films grown by different CH4/N2 ratios showed different morphology, which was revealed by scanning electron microscopy (SEM). The crystalline carbon nitride films containing silicon were realized using a CH4:N2 = 1:100 ratio. X-ray photoelectron spectroscopy (XPS), Auger electron microscopy (AES), Raman spectroscopy, and X-ray diffraction were used to characterize the composition and chemical bonding of the deposited films.

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