Electron field emission properties of nanodiamonds synthesized by the chemical vapor deposition process

2001 ◽  
Vol 19 (3) ◽  
pp. 975 ◽  
Author(s):  
Yu-Che Yu ◽  
Jin-Hua Huang ◽  
I-Nan Lin
Keyword(s):  
Chemical Vapor Deposition ◽  
Field Emission ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Electron Field Emission ◽  
Emission Properties ◽  
Field Emission Properties ◽  
Electron Field ◽  
Electron Field Emission Properties

SYNTHESIS OF GRAPHENE/DIAMOND DOUBLE-LAYERED STRUCTURE FOR IMPROVING ELECTRON FIELD EMISSION PROPERTIES

2016 ◽  
Vol 23 (03) ◽  
pp. 1650011
Author(s):  
YU QIAO ◽  
TING QI ◽  
JIE LIU ◽  
ZHIYONG HE ◽  
SHENGWANG YU ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Field Emission ◽  
Vapor Deposition ◽  
Microwave Plasma ◽  
Composite Films ◽  
Chemical Vapor ◽  
Grazing Incidence ◽  
Electron Field Emission ◽  
Field Emission Properties ◽  
Electron Field

Ultrananocrystalline diamond (UNCD) films on silicon were prepared by microwave plasma chemical vapor deposition (MPCVD) method using argon-rich CH4/H2/Ar plasmas. The graphene sheets synthesized by chemical vapor deposition (CVD) were successfully transferred on to the UNCD surface to fabricate electron field emission (EFE) property-enhanced graphene/UNCD films. The surface morphology, structure and composition of the graphene/UNCD double-layered structures were characterized by scanning electron microscope (SEM), atomic force microscope (AFM), Raman spectroscopy and grazing incidence X-ray diffraction (GXRD). GXRD clearly shows the characteristic diffraction peaks of both diamond and graphene. The Raman spectrum shows the characteristic band of diamond at 1332[Formula: see text]cm[Formula: see text] and D, G and 2D bands of graphene at 1360, 1550 and 2610[Formula: see text]cm[Formula: see text], respectively. The EFE behavior of the composite films can be turned on at [Formula: see text][Formula: see text]V/[Formula: see text]m, attaining a current density of 0.065[Formula: see text]mA/cm2 at an applied field of 7.3[Formula: see text]V/[Formula: see text]m.

Influence of sulfur incorporation on field-emission properties of microcrystalline diamond thin films

2003 ◽  
Vol 18 (11) ◽  
pp. 2708-2716 ◽  
Author(s):  
S. Gupta ◽  
B.R. Weiner ◽  
G. Morell
Keyword(s):  
Thin Films ◽  
Field Emission ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Electron Field Emission ◽  
Emission Properties ◽  
Field Emission Properties ◽  
Turn On ◽  
Electron Field ◽  
Diamond Thin Films

Results are reported on the electron field emission properties of microcrystalline diamond thin films grown on molybdenum substrates by the sulfur (S)-assisted hot-filament chemical vapor deposition technique using methane (CH4), hydrogen sulfide (H2S), and hydrogen (H2) gas mixtures. Electron field-emission measurements revealed that the S-incorporated microcrystalline diamond thin films have substantially lower turn-on fields and steep rising currents as compared to those grown without sulfur. The field-emission properties for the S-incorporated films were also investigated systematically as a function of substrate temperature (TS). Lowest turn-on field achieved was observed at around 12.5 V/μm for the samples grown at TS of 700°C with 500 ppm H2S. To establish the property-structure correlation, we analyzed the films with multiple characterizations include scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman spectroscopy (RS), and x-ray photoelectron spectroscopy (XPS) techniques. It was found that sulfur addition causes significant microstructural changes in microcrystalline diamond thin films. S-assisted films show smoother, coarse-grained surfaces (non-faceted) than those grown without it (well-faceted) and a relatively higher content of non-diamond carbon (primarily sp2-bonded C). RS and investigations on the morphology by SEM and AFM indicated the increase of sp2 C content with increasing TS followed by a morphological transition at 700°C in the films. XPS investigations also showed the incorporation of S in the films up to a few atomic layers. It is believed that the electron-emission properties are governed by the sulfur incorporation during the chemical vapor deposition process. Although most of the S is expected to be electrically inactive, under the high doping conditions hereby used, it is shown rather indirectly through multiple characterizations that there may be some amount of S in donor states. Therefore the results are discussed in terms of the dual role of S whereby it induces the structural defects in the form of enhanced sp2 C content at the expense of diamond quality and a possibility of availability of conduction electrons. In fact the latter finding is supported through room temperature electrical conductivity measurements.

Electron Field Emission Properties of Diamond

1995 ◽  
Vol 416 ◽  
Author(s):  
W. Zhu ◽  
G. P. Kochanski ◽  
S. Jin
Keyword(s):  
Field Emission ◽  
Electric Fields ◽  
Chemical Vapor ◽  
Electron Field Emission ◽  
Emission Data ◽  
Emission Properties ◽  
Field Emission Properties ◽  
Ultrafine Diamond ◽  
Electron Field ◽  
Electron Field Emission Properties

ABSTRACTWe have developed both experimental and numerical methods to collect and analyze field emission data from diamond samples. The diamond emitters are either films prepared by low pressure chemical vapor deposition (CVD) or powders synthesized by traditional high pressure high temperature (HPHT) processes. We established a strong correlation between the electric field required for emission and the defect densities in undoped or p-type doped diamond. We further found that ultrafine diamond particulate emitters offer substantially enhanced electron field emission properties at low electric fields compared to CVD diamond emitters. When subject to appropriate processing schemes, the particulate diamond emitters exhibit extremely low emission fields, typically 1-5 V/μm for a current density of 10 mA/cm2. These are believed to be the lowest-voltage field emitters ever reported.

Sign in / Sign up

Export Citation Format

Share Document