Field Emission Properties of Ion Beam Synthesized SiC/Si Heterostructures by MEVVA Implantation

1998 ◽  
Vol 509 ◽  
Author(s):  
Dihu Chen ◽  
S. P. Wong ◽  
W.Y. Cheung ◽  
E.Z. Luo ◽  
W. Wu ◽  
...  
Keyword(s):  
Field Emission ◽  
Photoelectron Spectroscopy ◽  
Ion Beam ◽  
Metal Vapor ◽  
Ion Source ◽  
Vacuum Arc ◽  
High Dose ◽  
Emission Properties ◽  
Field Emission Properties ◽  
Two Factors

AbstractPlanar SiC/Si heterostructures were formed by high dose carbon implantation using a metal vapor vacuum arc ion source. The variations of the field emission properties with the implant dose and annealing conditions were studied. A remarkably low turn-on field of IV/μm was observed from a sample implanted at 35 keV to a dose of 1.0×1018 cm−2 with subsequent annealing in nitrogen at 1200°C for 2h. The chemical composition depth profiles were determined from x-ray photoelectron spectroscopy and the surface morphology was observed by atomic force microscopy. The formation of a thin surface stoichiometric SiC layer and the formation of densely distributed small protrusions on the surface are believed to be the two factors responsible for the efficient electron field emission.

Effects of Beam Current Density on Ion Beam Synthesis OF SiC

2001 ◽  
Vol 680 ◽  
Author(s):  
D.H. Chen ◽  
S.P. Wong ◽  
J.K.N. Lindner
Keyword(s):  
Current Density ◽  
Photoelectron Spectroscopy ◽  
Ion Beam ◽  
Metal Vapor ◽  
Beam Current ◽  
Ion Source ◽  
Vacuum Arc ◽  
Beam Current Density ◽  
Carbon Clusters ◽  
High Dose

ABSTRACTThin SiC layers were synthesized by high dose C implantation into silicon using a metal vapor vacuum arc ion source at various conditions. Characterization of the ion beam synthesized SiC layers was performed using various techniques including x-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) absorption, and Raman spectroscopy. The XPS results showed that for samples with over-stoichiometric implant doses, if the implant beam current density was not high enough, even after prolonged thermal annealing at high temperatures, the as-implanted gaussian-like carbon depth profile remained unchanged. However, if the implant beam current density was sufficiently high, there was significant carbon redistribution during annealing, so that a thicker stoichiometric SiC layer can be formed after annealing. The XPS and Raman results also showed that there were carbon clusters formed in the as-implanted layers for the low beam current density implanted samples, while the formation of such carbon clusters was minimal in the high beam current density as-implanted samples. The effect of beam current density on the fraction of different bonding states of the implanted carbon atoms was studied.

Field Enhancement Mechanisms and Electron Field Emission Properties of Ion Beam Synthesized and Modified SiC/Si Heterostructures

2002 ◽  
Vol 742 ◽  
Author(s):  
W. M. Tsang ◽  
S. P. Wong ◽  
J. K. N. Lindner
Keyword(s):  
Field Emission ◽  
Ion Beam ◽  
Field Enhancement ◽  
Ion Source ◽  
High Dose ◽  
Electron Field Emission ◽  
Emission Properties ◽  
Field Emission Properties ◽  
Electron Field ◽  
Electron Field Emission Properties

ABSTRACTSiC/Si heterostructures were synthesized by high dose carbon implantation into silicon using a metal vapor vacuum arc ion source. Their electron field emission properties were studied and correlated with results from other characterization techniques including atomic force microscopy (AFM), conducting AFM, Fourier transform infrared absorption spectroscopy, x-ray diffraction and photoelectron spectroscopy. It is clearly demonstrated that there are two types of field enhancement mechanisms responsible for the improvement of the electron field emission properties of these ion beam synthesized SiC/Si heterostructures, namely, the surface morphology effect and the local electrical inhomogeneity effect. The dependence of the FE properties on the carbon implant dose and thermal annealing conditions could be understood in terms of these two field enhancement mechanisms. It is also demonstrated that improvement in the FE properties can be achieved by implanting tungsten ions into these SiC/Si heterostructures.

Structures and light emission properties of nanocrystalline FeSi2/Si formed by ion beam synthesis with a metal vapor vacuum arc ion source

2007 ◽  
Vol 515 (22) ◽  
pp. 8122-8128 ◽  
Author(s):  
S.P. Wong ◽  
C.F. Chow ◽  
Judith Roller ◽  
Y.T. Chong ◽  
Q. Li ◽  
...  
Keyword(s):  
Light Emission ◽  
Ion Beam ◽  
Metal Vapor ◽  
Ion Source ◽  
Vacuum Arc ◽  
Emission Properties ◽  
Ion Beam Synthesis

scholarly journals Formation of Buried Epitaxial Si-Ge Alloy Layers in Si Crystal by High Dose Ge ION Implantation

1991 ◽  
Vol 235 ◽  
Author(s):  
Kin Man Yu ◽  
Ian G. Brown ◽  
Seongil Im
Keyword(s):  
Ion Implantation ◽  
Single Crystal ◽  
Lattice Mismatch ◽  
Solid Phase ◽  
Metal Vapor ◽  
Ion Source ◽  
Vacuum Arc ◽  
High Dose ◽  
Solid Phase Epitaxy ◽  
Ion Channeling

ABSTRACTWe have synthesized single crystal Si1−xGex alloy layers in Si <100> crystals by high dose Ge ion implantation and solid phase epitaxy. The implantation was performed using the metal vapor vacuum arc (Mevva) ion source. Ge ions at mean energies of 70 and 100 keV and with doses ranging from 1×1016 to to 7×1016 ions/cm2 were implanted into Si <100> crystals at room temperature, resulting in the formation of Si1−xGex alloy layers with peak Ge concentrations of 4 to 13 atomic %. Epitaxial regrowth of the amorphous layers was initiated by thermal annealing at temperatures higher than 500°C. The solid phase epitaxy process, the crystal quality, microstructures, interface morphology and defect structures were characterized by ion channeling and transmission electron microscopy. Compositionally graded single crystal Si1−xGex layers with full width at half maximum ∼100nm were formed under a ∼30nm Si layer after annealing at 600°C for 15 min. A high density of defects was found in the layers as well as in the substrate Si just below the original amorphous/crystalline interface. The concentration of these defects was significantly reduced after annealing at 900°C. The kinetics of the regrowth process, the crystalline quality of the alloy layers, the annealing characteristics of the defects, and the strains due to the lattice mismatch between the alloy and the substrate are discussed.

Solid Phase Epitaxy of Implanted Si-Ge-C Alloys

1995 ◽  
Vol 388 ◽  
Author(s):  
Xiang Lu ◽  
Nathan W. Cheung
Keyword(s):  
Lattice Mismatch ◽  
Solid Phase ◽  
Metal Vapor ◽  
High Dose Rate ◽  
Ion Source ◽  
Vacuum Arc ◽  
High Dose ◽  
Solid Phase Epitaxy ◽  
Cross Sectional ◽  
Rutherford Back Scattering

AbstractSi1-x-yGexCy/Si heterostuctures were formed on Si (100) surface by Ge and C implantation with a high dose rate MEtal - Vapor Vacuum arc (MEVVA) ion source and subsequent Solid Phase Epitaxy (SPE). after thermal annealing in the temperature range from 600 °C to 1200 °C, the implanted layer was studied using Rutherford Back-scattering Spectrometry (RBS), cross-sectional High Resolution Transmission Electron Microscopy (HRTEM) and fourbounce X-ray Diffraction (XRD) measurement. Due to the small lattice constant and wide bandgap of SiC, the incorporation of C into Si-Ge can provide a complementary material to Si-Ge for bandgap engineering of Si-based heterojunction structure. Polycrystals are formed at temperature at and below 1000 °C thermal growth, while single crystal epitaxial layer is formed at 1100 °C and beyond. XRD measurements near Si (004) peak confirm the compensation of the Si1-x Gex lattice mismatch strain by substitutional C. C implantation is also found to suppress the End of Range (EOR) defect growth.

Effect of O2+, H2++ O2+, and N2++ O2+ ion-beam irradiation on the field emission properties of carbon nanotubes

2011 ◽  
Vol 109 (11) ◽  
pp. 114317 ◽  
Author(s):  
J. J. S. Acuña ◽  
M. Escobar ◽  
S. N. Goyanes ◽  
R. J. Candal ◽  
A. R. Zanatta ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Field Emission ◽  
Ion Beam ◽  
Beam Irradiation ◽  
Ion Beam Irradiation ◽  
Emission Properties ◽  
Field Emission Properties

Phase Transformation and Ion Beam Induced Crystallization in SiC Layers Formed by Mevva Implantation of Carbon into Silicon

1997 ◽  
Vol 481 ◽  
Author(s):  
Dihu Chen ◽  
S. P. Wong ◽  
L. C. Ho ◽  
H. Yan ◽  
R.W.M. Kwok
Keyword(s):  
Ion Beam ◽  
Strong Dependence ◽  
Metal Vapor ◽  
Ion Source ◽  
Vacuum Arc ◽  
Preparation Conditions ◽  
Random Nucleation ◽  
The One ◽  
Amorphous Sic ◽  
Induced Crystallization

ABSTRACTBuried SiC layers were synthesized by carbon implantation into silicon with a metal vapor vacuum arc ion source under various implantation and annealing conditions. The infrared absorption spectra of these samples were deconvoluted into two or three gaussian components depending on the preparation conditions. One component peaked at around 700 cm-1was assigned to amorphous SiC (a-SiC). The other two components, both peaked at 795 cm-1 but with different values of full width at half maximum (FWHM), were attributed to β-SiC. The one with a larger (smaller) FWHM corresponds to β-SiC of smaller (larger) grains. With this deconvolution scheme, the fraction of various SiC phases in these samples were determined. It was found that for the as-implanted samples there are critical energies and doses at which the crystalline SiC fraction increases abruptly. This was attributed to the ion beam induced crystallization (IBIC) effect. It was also shown that the IBIC effect leads to strong dependence of the β-SiC fraction on the order of implantation for samples synthesized by double-energy implantation. Analysis of the evolution of the β-SiC fraction with annealing time indicated that the crystallization process in these SiC layers could well be described by the classical random nucleation and growth theory.

Pattern Evolution of NiSi2 on Si Surface upon High Current Pulsed Ni Ion Implantation

2000 ◽  
Vol 648 ◽  
Author(s):  
X.Q. Cheng ◽  
H.N. Zhu ◽  
B.X. Liu
Keyword(s):  
Ion Implantation ◽  
Ion Beam ◽  
Fractal Dimensions ◽  
Metal Vapor ◽  
Ion Source ◽  
Vacuum Arc ◽  
High Current ◽  
Si Substrate ◽  
Kinetics Of ◽  
Si Wafer

AbstractFractal pattern evolution of NiSi2 grains on a Si surface was induced by high current pulsed Ni ion implantation into Si wafer using metal vapor vacuum arc ion source. The fractal dimension of the patterns was found to correlate with the temperature rise of the Si substrate caused by the implanting Ni ion beam. With increasing of the substrate temperature, the fractal dimensions were determined to increase from less than 1.64, to beyond the percolation threshold of 1.88, and eventually up to 2.0, corresponding to a uniform layer with fine NiSi2 grains. The growth kinetics of the observed surface fractals was also discussed in terms of a special launching mechanism of the pulsed Ni ion beam into the Si substrate.

CARBON NANOCOMPOSITE THIN FILMS PREPARED BY FILTERED CATHODIC VACUUM ARC TECHNIQUE

2002 ◽  
Vol 16 (06n07) ◽  
pp. 933-945 ◽  
Author(s):  
B. K. TAY ◽  
Y. H. CHENG ◽  
S. P. LAU ◽  
X. SHI
Keyword(s):  
Surface Energy ◽  
Internal Stress ◽  
Young’S Modulus ◽  
Field Emission ◽  
Young's Modulus ◽  
Vacuum Arc ◽  
Composite Target ◽  
Emission Properties ◽  
Field Emission Properties ◽  
Filtered Cathodic Vacuum Arc

Nanocomposite amorphous carbon (a-C:Me) films including a-C:Ni , a-C:Co , a-C:Ti , a-C:W , a-C:Fe , a-C:Al , and a-C:Si films were deposited using metal-carbon composite target by filtered cathodic vacuum arc (FCVA) technique. Atomic force microscopy (AFM), Raman, and X-ray photoelectron spectroscopy (XPS) were used to characterize the morphology and structure of the films. Nanoindenter and surface profilometer were used to determine the hardness, Young's modulus, and internal stress. Contact angle and field emission experiments were used to study the surface energy and field emission properties of the films respectively. The influence of the type of elements and its composition in the target on the structural, mechanical, surface energy, and field emission properties were studied. The incorporation of elements into the films results in the decrease of sp 3 C fraction, internal stress in the deposited films, but the hardness and Young's modulus remains at high level. The effect of non-carbide forming elements in the films on the mechanical properties is more pronounced than that of carbide forming elements. The surface energy of the films increases with incorporating Ni atoms, but decreases after incorporating Fe and Al atoms into the films. After heat treatment, the incorporation of metal into ta-C films can greatly improve the field emission performance.

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