Low-field electron emission from undoped nanostructured diamond

Science

Volumn 282, Issue 5393, 1998, Pages 1471-1473

  Zhu, W ^a   Kochanski, G P ^a   Jin, S ^a  

^a LUCENT TECHNOLOGIES   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

BAND STRUCTURE; CURRENT DENSITY; DIAMONDS; ELECTRIC FIELD EFFECTS; FERMI LEVEL; FIELD EMISSION CATHODES; HEAT TREATMENT; HYDROGEN; NANOSTRUCTURED MATERIALS; PLASMAS;

BORON DOPING; COLD CATHODE ELECTRON FIELD EMITTERS; ENERGY BARRIER; FIELD EMITTING MATERIAL; GEOMETRIC FIELD ENHANCEMENT; LOW ELECTRON AFFINITY; MICROPOLYCRYSTALLINE DIAMOND; NANOMETER SIZE; UNDOPED NANOSTRUCTURED DIAMOND;

ELECTRON EMISSION;

CARBON; DIAMOND;

ARTICLE; CHEMICAL STRUCTURE; ELECTRIC CURRENT; ELECTRIC FIELD; ELECTRON TRANSPORT; FILM; HEAT TREATMENT; MOLECULAR DYNAMICS; PRIORITY JOURNAL; STRUCTURE ANALYSIS;

EID: 0032553568     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.282.5393.1471     Document Type: Article

References (24)

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15. -8 torr base pressure at room temperature. As described previously (7), a voltage up to 2 kV was applied to a spherical-tipped molybdenum anode probe (tip radius of curvature ≅ 0.5 mm) to collect electrons emitted from the cathode diamond surface. A precision stepper controller (3.3 μm step size) was used to control the movement of the anode toward the cathode, and the emission current-voltage (I-V) characteristics were measured as a function of the anode-cathode distance. The obtained I-V data were analyzed using the Fowler-Nordheim theory (22), taking into consideration the variation of electrical field across the cathode surface and assuming a broad distribution in emission properties among the emitting tips (13). Capacitance was measured as the anode position changed to better determine the anode-cathode distance. A sphere-to-plane model was used to fit the capacitance data and estimate the position where the anode touched the cathode surface (13). The capacitance measurements also allowed problems - such as arcing, missteps of the probe, moving dust particles, or loose samples -to be detected, because they introduce discontinuities in an otherwise smooth capacitance-distance curve. The standard deviation of the capacitance about the fit corresponds to a 3 μm uncertainty out of a 100-μm spacing.
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