Simultaneous Field Emission and Photoemission Characterization of N-Doped CVD Diamond

1998 ◽  
Vol 509 ◽  
Author(s):  
Ryuichi Matsuda ◽  
Ken Okano ◽  
Bradford B. Pate

AbstractThe kinetic energy and spatial distribution of field electron emission from nitrogen (urea) doped, chemical vapor deposited (CVD) diamond films have been examined with simultaneous field emission and photoemission. A linear Fowler-Nordheim characteristic was measured over a wide range of currents. The field emission electrons originate from distinct areas of the flat sample. The dominant origin of field emission is due to electrons tunneling from near the valence band maximum. A time dependent fluctuation in the kinetic energy and spatial distribution of the emission is observed when the applied electric field (and hence emission current density) is increased well above the emission threshold.

1990 ◽  
Vol 5 (8) ◽  
pp. 1591-1594 ◽  
Author(s):  
A. V. Hetherington ◽  
C. J. H. Wort ◽  
P. Southworth

The crystalline perfection of microwave plasma assisted chemical vapor deposited (MPACVD) diamond films grown under various conditions has been examined by TEM. Most CVD diamond films thus far reported contain a high density of defects, predominantly twins and stacking faults on {111} planes. We show that under appropriate growth conditions, these planar defects are eliminated from the center of the crystallites, and occur only at grain boundaries where the growing crystallites meet.


2014 ◽  
Vol 1035 ◽  
pp. 3-6
Author(s):  
Jin Hai Gao ◽  
Zhen Li ◽  
Wu Qing Zhang

The sphere-like diamond microcrystalline-aggregates were fabricated by microwave plasma chemical vapor deposition (MPCVD) method. The ceramic with a Ti metal layer was used as substrates. The fabricated diamond microcrystalline aggregates were evaluated by Raman scattering spectroscopy, x-ray diffraction spectrum (XRD), scanning electron microscopy (SEM). The field emission properties were tested by using a diode structure in a vacuum. A phosphor-coated indium tin oxide (ITO) anode was used for observing and characterizing the field emission. It was found that the sphere-like diamond microcrystalline-aggregates films exhibited good electron emission properties. The turn-on field was only 0.55V/μm, and emission current density as high as 11mA/cm2 was obtained under an applied field of 2.18V/μm for the first operation. After several cycling operations, the field emission tended to stable characteristics of current versus voltage. The stability evolvement and mechanism are investigated relating to microstructure of the sphere-like diamond microcrystalline-aggregates films.


1993 ◽  
Vol 2 (5-7) ◽  
pp. 1059-1063 ◽  
Author(s):  
J.E. Graebner ◽  
S. Jin ◽  
G.W. Kammlott ◽  
Y.-H. Wong ◽  
J.A. Herb ◽  
...  

2005 ◽  
Vol 901 ◽  
Author(s):  
Han Zhang ◽  
Jie Tang ◽  
Qi Zhang ◽  
Gongpu Zhao ◽  
Guang Yang ◽  
...  

AbstractFor field-induced electron emission, the two factors that enable a high emission current density at low applied voltages are (a) low work function of the emitter and (b) sharpness of the emitter tip. We have developed and applied a chemical vapor deposition method to synthesize single-crystalline LaB6 nanowires for applications as point electron emitters. The crystallographic orientation of the grown nanowires can be controlled by the catalysts used in synthesis and their typical diameter is ranged from below 20 nm to over 100 nm. The nanowires’ tip is either hemispherical or flat top with rectangular cross-section depending on the catalyst being utilized. The field emission properties have also been measured from the single nanowire emitters and the results are discussed for applications as point electron sources used in high performance electron optical instruments such as the transmission and scanning electron microscopes.


1993 ◽  
Vol 302 ◽  
Author(s):  
S. Zhao ◽  
K.K. Gan ◽  
H. Kagan ◽  
R. Kass ◽  
R. Malchow ◽  
...  

ABSTRACTThe electrical properties associated with carrier mobility, μ, and lifetime, τ, have been investigated for the chemical vapor deposited (CVD) diamond films using charged particle-induced conductivity and time resolved transient photo-induced conductivity. The collection distance, d, the average distance which electron and hole depart when driven by an applied electric field E, was measured by both methods. The collection distance is related to the carrier mobility and lifetime by d = μEτ Our measurements show that the collection distance increases linearly with sample thickness for CVD diamond films. The collection distance at the growth side of the CVD diamond film is comparable to that of single crystal natural type IIa diamond; at the substrate side of the film, the collection distance is near zero. No saturation of the collection distance is observed for film thickness up to 500 microns.


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