Surface morphology of ion-beam deposited carbon films under high temperature

AbstractThe principal interests in this work are energetic-beam control of carbon-film properties and the roles of doping and surface morphology in field emission. Carbon films with variable sp3-bonding fraction were deposited on n-type Si substrates by ArF (193 nm) pulsed-laser ablation (PLA) of a pyrolytic graphite target, and by direct metal ion beam deposition (DMIBD) using a primary Cs+ beam to generate the secondary C- deposition beam. The PLA films are undoped while the DMIBD films are doped with Cs. The kinetic energy (KE) of the incident C atoms/ions was controlled and varied over the range from ∼25 eV to ∼175 eV. Earlier studies have shown that C films' sp3-bonding fraction and diamond-like properties can be maximized by using KE values near 90 eV. The films' surface morphology, sp3–bonding fraction, and Cs-content were determined as a function of KE using atomic force microscopy, TEM/EELS, Rutherford backscattering and nuclear reaction measurements, respectively. Field emission (FE) from these very smooth undoped and Cs-containing films is compared with the FE from two types of deliberately nanostructured carbon films, namely hot-filament chemical vapor deposition (HF-CVD) carbon and carbon nanotubes grown by plasma-enhanced CVD. Electron field emission (FE) characteristics were measured using ∼25-μm, ∼5-μm and ∼1-μm diameter probes that were scanned with ∼75 nm resolution in the x-, y-, and z-directions in a vacuum chamber (∼5 × 10-7 torr base pressure) equipped with a video camera for viewing. The hydrogen-free and very smooth a-D or a-C films (with high or low sp3 content, and with or without ∼1% Cs doping) produced by PLD and DMIBD are not good field emitters. Conditioning accompanied by arcing was required to obtain emission, so that their subsequent FE is characteristic of the arc-produced damage site. However, deliberate surface texturing can eliminate the need for conditioning, apparently by geometrical enhancement of the local electric field. But the most promising approach for producing macroscopically flat FE cathodes is to use materials that are highly nanostructured, either by the deposition process (e.g. HF-CVD carbon) or intrinsically (e.g. carbon nanotubes). HF-CVD films were found to combine a number of desirable properties for FE displays and vacuum microelectronics, including the absence of conditioning, low turn-on fields, high emission site density, and apparent stability and durability during limited long-term testing. Preliminary FE measurements revealed that vertically aligned carbon nanotubes are equally promising.

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Synthesis of Diamond Like Carbon Films Deposited by the Ionization Vapor Method and Development of its Semiconductive Devices Fabricated by the Focused Ga-ion Beam Implantation

IEEJ Transactions on Fundamentals and Materials ◽

10.1541/ieejfms.137.584 ◽

2017 ◽

Vol 137 (10) ◽

pp. 584-589

Author(s):

Satoshi Kurumi ◽

Yusuke Takahara ◽

Takafumi Ohno ◽

Ken-ichi Matsuda ◽

Kaoru Suzuki

Keyword(s):

Ion Beam ◽

Carbon Films ◽

Diamond Like Carbon ◽

Ion Beam Implantation ◽

Vapor Method

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Carbon Film Deposition On Silicon Using Low Energy Ion Beams

MRS Proceedings ◽

10.1557/proc-223-307 ◽

1991 ◽

Vol 223 ◽

Author(s):

Qin Fuguang ◽

Yao Zhenyu ◽

Ren Zhizhang ◽

S.-T. Lee ◽

I. Bello ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Ion Beam ◽

Carbon Film ◽

Carbon Films ◽

Film Deposition ◽

Ion Energy ◽

Transmission Electron ◽

Higher Temperature ◽

Post Implantation ◽

Beam Deposition

ABSTRACTDirect ion beam deposition of carbon films on silicon in the ion energy range of 15–500eV and temperature range of 25–800°C has been studied using mass selected C+ ions under ultrahigh vacuum. The films were characterized with X-ray photoelectron spectroscopy, Raman spectroscopy, and transmission electron microscopy and diffraction analysis. Films deposited at room temperature consist mainly of amorphous carbon. Deposition at a higher temperature, or post-implantation annealing leads to formation of microcrystalline graphite. A deposition temperature above 800°C favors the formation of microcrystalline graphite with a preferred orientation in the (0001) direction. No evidence of diamond formation was observed in these films.

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Nanocomposite Polyurethane Foams Via POSS Blends

MRS Proceedings ◽

10.1557/proc-733-t1.6 ◽

2002 ◽

Vol 733 ◽

Author(s):

Brock McCabe ◽

Steven Nutt ◽

Brent Viers ◽

Tim Haddad

Keyword(s):

High Temperature ◽

Sample Preparation ◽

Room Temperature ◽

Focused Ion Beam ◽

Ion Beam ◽

Polyurethane Foams ◽

Development Projects ◽

Polymer Systems ◽

Polyurethane Resin ◽

Military Development

AbstractPolyhedral Oligomeric Silsequioxane molecules have been incorporated into a commercial polyurethane formulation to produce nanocomposite polyurethane foam. This tiny POSS silica molecule has been used successfully to enhance the performance of polymer systems using co-polymerization and blend strategies. In our investigation, we chose a high-temperature MDI Polyurethane resin foam currently used in military development projects. For the nanofiller, or “blend”, Cp7T7(OH)3 POSS was chosen. Structural characterization was accomplished by TEM and SEM to determine POSS dispersion and cell morphology, respectively. Thermal behavior was investigated by TGA. Two methods of TEM sample preparation were employed, Focused Ion Beam and Ultramicrotomy (room temperature).

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An Study of Influence of Imperfections on the Delamination of Diamond-Like Carbon Films

MRS Proceedings ◽

10.1557/proc-719-f8.36 ◽

2002 ◽

Vol 719 ◽

Author(s):

Myoung-Woon Moon ◽

Kyang-Ryel Lee ◽

Jin-Won Chung ◽

Kyu Hwan Oh

Keyword(s):

Cross Sections ◽

Focused Ion Beam ◽

Imaging System ◽

Ion Beam ◽

Carbon Films ◽

Diamond Like Carbon ◽

Glass Substrates ◽

Atomic Force ◽

Initiation And Propagation

AbstractThe role of imperfections on the initiation and propagation of interface delaminations in compressed thin films has been analyzed using experiments with diamond-like carbon (DLC) films deposited onto glass substrates. The surface topologies and interface separations have been characterized by using the Atomic Force Microscope (AFM) and the Focused Ion Beam (FIB) imaging system. The lengths and amplitudes of numerous imperfections have been measured by AFM and the interface separations characterized on cross sections made with the FIB. Chemical analysis of several sites, performed using Auger Electron Spectroscopy (AES), has revealed the origin of the imperfections. The incidence of buckles has been correlated with the imperfection length.

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Evaluation of the sub-surface morphology and composition of gunshot residue using focussed ion beam analysis

Forensic Science International ◽

10.1016/j.forsciint.2019.01.030 ◽

2019 ◽

Vol 297 ◽

pp. 100-110 ◽

Cited By ~ 2

Author(s):

Nick Lucas ◽

Kelsey E. Seyfang ◽

Andrew Plummer ◽

Michael Cook ◽

K. Paul Kirkbride ◽

...

Keyword(s):

Surface Morphology ◽

Ion Beam ◽

Gunshot Residue ◽

Ion Beam Analysis ◽

Beam Analysis ◽

Focussed Ion Beam

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Characterization and Performance of Carbon Films Deposited by Plasma and Ion Beam Based Techniques

MRS Proceedings ◽

10.1557/proc-354-87 ◽

1994 ◽

Vol 354 ◽

Cited By ~ 7

Author(s):

K.C. Walter ◽

H. Kung ◽

T. Levine ◽

J.T. Tesmer ◽

P. Kodali ◽

...

Keyword(s):

Wear Rate ◽

Surface Area ◽

Ion Beam ◽

Carbon Films ◽

The Self ◽

Line Of Sight ◽

Rf Power ◽

Hard Carbon ◽

Self Bias ◽

Cathodic Arc

AbstractPlasma and ion beam based techniques have been used to deposit carbon-based films. The ion beam based method, a cathodic arc process, used a magnetically mass analyzed beam and is inherently a line-of-sight process. Two hydrocarbon plasma-based, non-line-of-sight techniques were also used and have the advantage of being capable of coating complicated geometries. The self-bias technique can produce hard carbon films, but is dependent on rf power and the surface area of the target. The pulsed-bias technique can also produce hard carbon films but has the additional advantage of being independent of rf power and target surface area. Tribological results indicated the coefficient of friction is nearly the same for carbon films from each deposition process, but the wear rate of the cathodic arc film was five times less than for the self-bias or pulsed-bias films. Although the cathodic arc film was the hardest, contained the highest fraction of sp3 bonds and exhibited the lowest wear rate, the cathodic arc film also produced the highest wear on the 440C stainless steel counterface during tribological testing. Thus, for tribological applications requiring low wear rates for both counterfaces, coating one surface with a very hard, wear resistant film may detrimentally affect the tribological behavior of the counterface.

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Large Area Surface Treatment by Ion Beam Technology

MRS Proceedings ◽

10.1557/proc-438-611 ◽

1996 ◽

Vol 438 ◽

Cited By ~ 2

Author(s):

R. L. C. Wu ◽

W. Lanter

Keyword(s):

Ion Beam ◽

High Vacuum ◽

Polycrystalline Diamond ◽

Carbon Films ◽

Ultra High Vacuum ◽

Diamond Like Carbon ◽

Chemical Compositions ◽

Rf Power ◽

Large Area ◽

Ion Energy

AbstractAn ultra high vacuum ion beam system, consisting of a 20 cm diameter Rf excilted (13.56 MHz) ion gun and a four-axis substrate scanner, has been used to modify large surfaces (up to 1000 cm2) of various materials, including; infrared windows, silicon nitride, polycrystalline diamond, 304 and 316 stainless steels, 440C and M50 steels, aluminum alloys, and polycarbonates; by depositing different chemical compositions of diamond-like carbon films. The influences of ion energy, Rf power, gas composition (H2/CH4 , Ar/CH4 and O2/CH4/H2), on the diamond-like carbon characteristics has been studied. Particular attention was focused on adhesion, environmental effects, IR(3–12 μm) transmission, coefficient of friction, and wear factors under spacelike environments of diamond-like carbon films on various substrates. A quadrupole mass spectrometer was utilized to monitor the ion beam composition for quality control and process optimization.

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