In-Situ Characterization of Thin Polycrystalline Diamond Film Quality by Thermal Wave and Raman Techniques

1989 ◽  
Vol 162 ◽  
Author(s):  
R. W. Pryor ◽  
P. K. Kuo ◽  
L. Wei ◽  
R. L. Thomas ◽  
P. L. Talley
Keyword(s):  
Thermal Conductivity ◽  
Laser Beam ◽  
Probe Beam ◽  
Diamond Film ◽  
Thermal Wave ◽  
Diamond Films ◽  
Film Surface ◽  
Polycrystalline Diamond ◽  
Probe Laser ◽  
Wave Technique

ABSTRACTIn this paper, the thermal wave technique and microfocus Raman spectroscopy are used to measure the relative quality of thin diamond films deposited on silicon. The thermal wave technique uses a modulated heating laser beam, normal to the diamond film surface, to initiate a thermal wave which propagates into the film, the substrate, and the overlying gas(ses). The accompanying modulated gas density is then interrogated by a second (probe) laser beam. The probe beam is deflected by the corresponding periodic changes in the gradient of the refractive index of the gas. The measured probe beam deflection versus offset position is fitted, using a theoretical solution of the three-dimensional thermal diffusion equation for the gas/film/substrate system. The physically important fitting parameter is the thermal diffusivity of the diamond film. Thermal conductivities derived from our diffusivity measurements using this method compare well to previous measurements on similarly prepared films by other methods. Our measured values for the thermal conductivity of the highest-quality polycrystalline diamond films are of the order of 12 W/cm-K. Our measured values of thermal conductivity for diamond films range between this value and the thermal conductivity of graphite. We have also made measurements on bulk diamond using the thermal wave technique, and we obtain a thermal conductivity of 21 W/cm-K, in excellent agreement with values found in the literature. A multi-scan, microfocus ratio of “graphitic” material to diamond material for a relative assessment of film quality.

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.

Two-dimensional reconstruction theory of thermal conductivity profiles based on the thermal wave technique

2002 ◽  
Vol 92 (7) ◽  
pp. 4088-4094 ◽  
Author(s):  
Q. B. Zhou ◽  
Y. K. Lu ◽  
S. Y. Zhang ◽  
J. C. Cheng ◽  
X. J. Shui
Keyword(s):  
Thermal Conductivity ◽  
Thermal Wave ◽  
Two Dimensional ◽  
Dimensional Reconstruction ◽  
Wave Technique

The thermal conductivity of polycrystalline diamond films: Effects of isotope content

1996 ◽  
Vol 79 (11) ◽  
pp. 8336-8340 ◽  
Author(s):  
Kalayu Belay ◽  
Zongyin Etzel ◽  
David G. Onn ◽  
T. R. Anthony
Keyword(s):  
Thermal Conductivity ◽  
Diamond Films ◽  
Polycrystalline Diamond ◽  
Isotope Content

Polycrystalline Diamond Film Resistors

1992 ◽  
Vol 242 ◽  
Author(s):  
L. M. Edwards ◽  
J. L. Davidson
Keyword(s):  
Diamond Film ◽  
Microwave Plasma ◽  
Diamond Films ◽  
Polycrystalline Diamond ◽  
Plasma Cvd ◽  
Microwave Plasma Cvd ◽  
P Type ◽  
Polycrystalline Diamond Film ◽  
Effective Source

ABSTRACTThe technology to fabricate polycrystalline diamond film resistors has been initiated using modified thick film patterning techniques and in situ solid source doping.Doping of polycrystalline diamond films in microwave plasma CVD systems has been achieved historically through use of diborane gas, which may contaminate the deposition system causing all diamond films thereafter to be doped p-type. We have attempted noncontaminating in situ doping utilizing two solid source dopants, and have met with preliminary success.The more effective source (B2O3) produces a fairly even dopant concentration across the substrate, with sheet resistances ranging from 800 ohms per square to 4500 ohms per square. The other source (BN) showed significant doping in a narrow band surrounding the source, but the doping concentration decreased rapidly with distance from the source. Films grown afterwards with no doping were evaluated through resistance measurements; no evidence of doping contamination was observed.

Influence of structural characteristics on the thermal conductivity of polycrystalline diamond films

1998 ◽  
Vol 40 (7) ◽  
pp. 1112-1116 ◽  
Author(s):  
A. N. Obraztsov ◽  
I. Yu. Pavlovskii ◽  
H. Okushi ◽  
H. Watanabe
Keyword(s):  
Thermal Conductivity ◽  
Structural Characteristics ◽  
Diamond Films ◽  
Polycrystalline Diamond

Formation of diffractive microrelief on diamond film surface for IR laser beam control

2006 ◽  
Author(s):  
A. V. Volkov ◽  
S. A. Borodin ◽  
G. F. Kostyuk ◽  
V. S. Pavelyev
Keyword(s):  
Laser Beam ◽  
Diamond Film ◽  
Film Surface ◽  
Beam Control ◽  
Ir Laser

Study on EDM Polishing of CVD Diamond Films

2006 ◽  
Vol 315-316 ◽  
pp. 464-468 ◽  
Author(s):  
Wen Zhuang Lu ◽  
Dun Wen Zuo ◽  
Min Wang ◽  
Feng Xu ◽  
Xiang Feng Li
Keyword(s):  
Diamond Film ◽  
Discharge Current ◽  
Material Removal ◽  
Diamond Films ◽  
Film Surface ◽  
Chemical Vapor ◽  
Cvd Diamond ◽  
Machined Surface ◽  
Cvd Diamond Film ◽  
Pulse On Time

Chemical vapor deposition (CVD) diamond is known for its superior characteristics such as hardness, toughness and wear resistance. However, due to these factors, machining CVD diamond is a difficult material removal process. A new technique to polish CVD diamond film efficiently is reported in the present paper. In the CVD deposition process, boron was doped into diamond to fabricate high-quality semi-conductive film, which make it possible to machine diamond film by electro discharged machining (EDM) method. The relationship between EDM parameter and removal processing was investigated in details. The machined surface of boron doped (B-doped) diamond films was studied by Scanning Electron Microscope (SEM) and Raman Scattering Spectroscopy (Raman). The experimental results show that EDM polishing is a highspeed material removal and low cost method for CVD diamond polishing. When the discharge current and pulse-on time increase in a certain range, the cutting-off speed and roughness will increase correspondingly. The roughness of EDM polished CVD diamond film surface is Ra<0.5μm when the discharge current is at 4A and pulse-on time is at 200μs.

Microstructure of polycrystalline diamond film

1990 ◽  
Vol 48 (4) ◽  
pp. 708-709
Author(s):  
M. G. Burke ◽  
R. E. Witkowski ◽  
R. T. Blackham
Keyword(s):  
Electron Microscopy ◽  
Diamond Film ◽  
Microwave Plasma ◽  
Plasma Deposition ◽  
Analytical Electron Microscopy ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Optical Systems ◽  
Power Sources

Diamond films have attracted considerable attention for use in a wide variety of industrial and commercial applications, particularly as coatings. Diamond coatings will enhance the performance of electro-optical systems, space-based photovoltaic power sources, packages for power electronic devices, and wear-limited processing equipment. These films are generally grown via plasma deposition or chemical vapor deposition techniques using a mixture. To characterize the as-grown diamond films, a variety of techniques including transmission electron microscopy are utilized. For this study, films were grown in a 1.5 kW ASTeX High Pressure Microwave Plasma Source equipped with an austenitic stainless steel, quartz lined reaction chamber. The plasma was a mixture of 0.5 or 2.0% CH4 in H2 at a reactor pressure of 30-50 mm Hg. During deposition, the substrate was heatea to ∼900-950°C. It has been reported that variations in the growth conditions will markedly affect the microstructure of the diamond film; several film morphologies have been observed. The quality of the substrate also exerts a strong effect on the nucleation of the diamond. In this on-going study, the influence of film thickness on the microstructure of polycrystalline diamond films has been characterized by analytical electron microscopy.

Tribological characteristics of polycrystalline diamond films produced by chemical vapor deposition

1992 ◽  
Vol 7 (7) ◽  
pp. 1769-1777 ◽  
Author(s):  
M. Kohzaki ◽  
K. Higuchi ◽  
S. Noda ◽  
K. Uchida
Keyword(s):  
Friction Coefficient ◽  
Diamond Film ◽  
Room Temperature ◽  
Diamond Films ◽  
Polycrystalline Diamond ◽  
Diamond Surface ◽  
Tribological Characteristics ◽  
Test Environment ◽  
Friction Coefficients ◽  
Aisi 52100

Effects of surface roughness and crystallinity of polycrystalline diamond films on their tribological characteristics, as well as the effects of test environment, have been investigated. Friction and wear characteristics of the diamond films deposited on sintered SiC disks have been examined with a ball-on-disk tester in the absence of any lubricant. The friction coefficients of polished diamond films against SiC and Si3N4 balls were below 0.10 at room temperature while those of as-deposited films were around 0.20. The specific wear of counterparts on the polished film was five orders of magnitude smaller than on the as-deposited film. The friction coefficient between the polished diamond film and a AISI 52100 steel ball was about 0.20. Transfer of a small amount of AISI 52100 material to the diamond film was observed along the wear track of the polished diamond surface. Diamond films of high quality were more resistant to wear than the ones of low quality. On the other hand, the friction coefficients were not affected by the crystallinity of the diamond films in the present study. Tribological characteristics of the diamond films deteriorated with increasing sliding speed and ambient temperature. At 600 °C in dry N2, the friction coefficient of diamond films against a SiC ball was about 0.8, which was about ten times higher than that at room temperature in air.

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