Seeding With a Diamond Suspension for Growth of Smooth Polycrystalline Diamond Surfaces

1996 ◽  
Vol 423 ◽  
Author(s):  
I. St. Omer ◽  
T. Stacy ◽  
E. M. Charlson ◽  
E. J. Charlson
Keyword(s):  
Surface Roughness ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Diamond Powder ◽  
Diamond Surface ◽  
Nucleation Density ◽  
Diamond Grit ◽  
Diamond Surfaces ◽  
Carrier Fluid

AbstractA number of techniques have been used to smooth polycrystalline diamond films. Recent work in substrate seeding with nanocrystalline diamond powder, alone or in a carrier fluid, has shown that diamond seeding improves nucleation density and reduces diamond surface roughness. In this work, silicon substrates were seeded using a commercially available waterbased 0.1 micrometer diamond polishing suspension. Growth was achieved using conventional hot-filament chemical vapor deposition (HFCVD). Films were characterized using optical microscopy, scanning electron microscopy (SEM), x-ray diffraction (XRD), and surface profilometry. The resulting diamond films exhibited well-faceted crystals, small grain size and minimal surface roughness. Additionally, the silicon substrate was chemically etched in order to permit examination of the backside of the diamond film. Results show that the diamond surface at the silicon-diamond interface is ultra-smooth. Comparison of the backside of these surfaces with those prepared using conventional diamond grit abrasion indicates that a significant improvement in surface quality is achieved using this diamond seeding technique.

Electronic Structure of Polycrystalline PECVD Diamond Surfaces

1995 ◽  
Vol 416 ◽  
Author(s):  
T. P. Humphreys ◽  
D. P. Malta ◽  
R. E. Thomas ◽  
J. B. Posthill ◽  
M. J. Mantini ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Electron Emission ◽  
Hydrogen Plasma ◽  
High Vacuum ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Low Energy ◽  
Diamond Surfaces ◽  
Single Crystal Diamond

ABSTRACTUltraviolet and X-ray photoelectron spectroscopy techniques have been employed in a preliminary study of the electronic structure of polycrystalline diamond films that have been grown on Si substrates by if-plasma enhanced chemical vapor deposition using water/ethanol growth chemistries. In particular, polycrystalline diamond films with distinctly different surface morphologies and Raman scattering characteristics have been investigated. Corresponding ultraviolet photoemission spectra from air-exposed samples have shown the presence of a prominent low-energy secondary electron emission peak indicative of a negative electron affinity (NEA) surface. Chemical stability of the polycrystalline diamond NEA surface has been demonstrated following conventional acid cleans and hydrogen plasma processing. In contrast, an oxygen (20%)/Ar plasma exposure has been shown to extinguish the photoemission of low-energy secondary electrons and remove the NEA. However, by employing a high-temperature anneal at 750 °C for 15 min in ultra-high vacuum the NEA surface can be restored. Compared to NEA single crystal diamond surfaces the photoexcited low-energy electron emission from chemical vapor deposited polycrystalline diamond films is more robust.

Characterization of homoepitaxial diamond films by Electron microscopy

1991 ◽  
Vol 49 ◽  
pp. 880-881
Author(s):  
D.P. Malta ◽  
S.A. Willard ◽  
R.A. Rudder ◽  
G.C. Hudson ◽  
J.B. Posthill ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Surface Defects ◽  
Substrate Surface ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Large Degree ◽  
Rf Plasma ◽  
Semiconducting Diamond

Semiconducting diamond films have the potential for use as a material in which to build active electronic devices capable of operating at high temperatures or in high radiation environments. A major goal of current device-related diamond research is to achieve a high quality epitaxial film on an inexpensive, readily available, non-native substrate. One step in the process of achieving this goal is understanding the nucleation and growth processes of diamond films on diamond substrates. Electron microscopy has already proven invaluable for assessing polycrystalline diamond films grown on nonnative surfaces.The quality of the grown diamond film depends on several factors, one of which is the quality of the diamond substrate. Substrates commercially available today have often been found to have scratched surfaces resulting from the polishing process (Fig. 1a). Electron beam-induced current (EBIC) imaging shows that electrically active sub-surface defects can be present to a large degree (Fig. 1c). Growth of homoepitaxial diamond films by rf plasma-enhanced chemical vapor deposition (PECVD) has been found to planarize the scratched substrate surface (Fig. 1b).

Examination of the material properties and performance of thin-diamond film cutting tool inserts produced by arc-jet and hot filament chemical vapor deposition

1996 ◽  
Vol 11 (7) ◽  
pp. 1765-1775 ◽  
Author(s):  
James M. Olson ◽  
Michael J. Dawes
Keyword(s):  
Wear Resistance ◽  
Chemical Vapor Deposition ◽  
Diamond Film ◽  
Vapor Deposition ◽  
Cutting Tool ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
And Performance ◽  
Hot Filament

Thin diamond film coated WC-Co cutting tool inserts were produced using arc-jet and hot-filament chemical vapor deposition. The diamond films were characterized using SEM, XRD, and Raman spectroscopy to examine crystal structure, fracture mode, thickness, crystalline orientation, diamond quality, and residual stress. The performance of the tools was evaluated by comparing the wear resistance of the materials to brazed polycrystalline diamond-tipped cutting tool inserts (PCD) while machining A390 aluminum (18% silicon). Results from the experiments carried out in this study suggest that the wear resistance of the thin diamond films is primarily related to the grain boundary strength, crystal orientation, and the density of microdefects in the diamond film.

A Comparative Study of Nucleation Enhancement Techniques for Plasma Cvd of Diamond Thin Films

1994 ◽  
Vol 349 ◽  
Author(s):  
R.J. Meilunas ◽  
A. Tobin
Keyword(s):  
Thin Film ◽  
Microwave Plasma ◽  
Chemical Vapor ◽  
Processing Parameters ◽  
Carbon Cluster ◽  
Nucleation Density ◽  
Plasma Cvd ◽  
Diamond Nucleation ◽  
Diamond Surfaces ◽  
Dc Biasing

ABSTRACTThree methods recently proposed for enhancing the nucleation density of thin film diamond on non-diamond surfaces during microwave plasma assisted chemical vapor deposition are investigated. The results of a series of nucleation and growth studies utilizing a dc biasing technique, carbon cluster (C70) thin film overlayers, and thin film metal (Fe) overlayers for diamond nucleation enhancement are presented. The influence of the substrate and plasma processing parameters under which the above nucleation enhancement effects occur has been determined for the three respective techniques.

Characterization of undoped and boron-doped polycrystalline diamond films synthesized by hot-filament chemical vapor deposition using methanol

1994 ◽  
Vol 3 (4-6) ◽  
pp. 618-622 ◽  
Author(s):  
Takashi Sugino ◽  
Kiyoshi Karasutani ◽  
Fumihiro Mano ◽  
Hiroya Kataoka ◽  
Junji Shirafuji ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Boron Doped ◽  
Hot Filament

Fracture strength and toughness of chemical-vapor-deposited polycrystalline diamond films

2018 ◽  
Vol 44 (15) ◽  
pp. 17845-17851 ◽  
Author(s):  
Kang An ◽  
Liangxian Chen ◽  
Xiongbo Yan ◽  
Xin Jia ◽  
Jinlong Liu ◽  
...  
Keyword(s):  
Fracture Strength ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Chemical Vapor Deposited ◽  
Strength And Toughness

scholarly journals Influence of the Heat Dissipation Mode of Long-Flute Cutting Tools on Temperature Distribution during HFCVD Diamond Films

Crystals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 394
Author(s):  
Zhang ◽  
Qian ◽  
wang ◽  
Huang ◽  
Zhang ◽  
...  
Keyword(s):  
Heat Dissipation ◽  
Focal Point ◽  
Cutting Tools ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Decisive Role ◽  
Diamond Coatings ◽  
The Difference ◽  
The Individual

The distribution of substrate temperature plays a decisive role on the uniformity of polycrystalline diamond films on cemented carbide tools with a long flute, prepared by a hot filament chemical vapor deposition (HFCVD). In this work, the heat dissipation mode at the bottom of tools is a focal point, and the finite volume method (FVM) is conducted to simulate and predict the temperature field of tools, with the various materials of the holder placed under the tools. The simulation results show that the thermal conductivity of the holder affects the temperature difference of the individual tools greatly, but only affects the temperature of different tools at the same XY plane slightly. Moreover, the ceramic holder can reduce the difference in temperature of an individual tool by 54%, compared to a copper one. Afterwards, the experiments of the deposition of diamond films is performed using the preferred ceramic holder. The diamond coatings on the different positions present a highly uniform distribution on their grain size, thickness, and quality.

Growth of Highly (110) Oriented Diamond Film by Microwave Plasma Chemical Vapor Deposition

2018 ◽  
Vol 281 ◽  
pp. 893-899 ◽  
Author(s):  
Yi Fan Xi ◽  
Jian Huang ◽  
Ke Tang ◽  
Xin Yu Zhou ◽  
Bing Ren ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Microwave Plasma ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Nucleation Density ◽  
Plasma Chemical ◽  
Plasma Chemical Vapor Deposition ◽  
Si Substrates ◽  
Nucleation Stage

In this study, we propose a simple and effective approach to enhance (110) orientation in diamond films grown on (100) Si substrates by microwave plasma chemical vapor deposition. It is found that the crystalline structure of diamond films strongly rely on the CH4 concentration in the nucleation stage. Under the same growth condition, when the CH4 concentration is less than 7% (7%) in the nucleation stage, the diamond films exhibit randomly oriented structure; once the value exceeds 7%, the deposited films are strongly (110) oriented. It could be verified by experiments that the formation of (110) orientation in diamond films are related to the high nucleation density and high fraction of diamond-like carbon existing in nucleation samples.

Coalesced oriented diamond films on nickel

1998 ◽  
Vol 13 (5) ◽  
pp. 1120-1123 ◽  
Author(s):  
P. C. Yang ◽  
C. A. Wolden ◽  
W. Liu ◽  
R. Schlesser ◽  
R. F. Davis ◽  
...  
Keyword(s):  
Gas Phase ◽  
Profile Analysis ◽  
Substrate Surface ◽  
Diamond Films ◽  
Diamond Powder ◽  
Hydrogen Atmosphere ◽  
Nucleation Density ◽  
Annealing Stage ◽  
Multistep Process ◽  
Degree Of Orientation

The growth of coalesced, highly oriented diamond films has been achieved on nickel substrates using a multistep process that consisted of (i) seeding the Ni surface with 0.5 μm diamond powder, (ii) annealing at 1100 °C in a hydrogen atmosphere, and (iii) growth at 900 °C in a mixture of hydrogen and 0.5% methane. Auger depth profile analysis of a sample quenched after the annealing stage showed the presence of significant amounts of carbon (6 at. %) close to the substrate surface and about 3 at.% deeper in the substrate. The loss of carbon into the substrate resulted in relatively low nucleation density. The addition of methane into the gas phase during the annealing stage proved very effective in compensating for the diffusion. An addition of 0.5% methane in the gas phase produced optimum results, as the nucleation density, orientation of diamond particles, and uniformity were substantially improved. Substrates nucleated under these conditions were grown out into coalesced, 30 μm thick films. Both (100) and (111) oriented films showed a high degree of orientation and Raman spectra obtained from these orientations showed intense and narrow diamond signature peaks with FWHM's of 5 and 8 cm-1, respectively.

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