Measurement of thermal diffusivity of polycrystalline diamond film by the converging thermal wave technique

1991 ◽  
Vol 59 (13) ◽  
pp. 1556-1558 ◽  
Author(s):  
Grant Lu ◽  
Walter T. Swann
Keyword(s):  
Thermal Diffusivity ◽  
Diamond Film ◽  
Thermal Wave ◽  
Polycrystalline Diamond ◽  
Wave Technique ◽  
Polycrystalline Diamond Film

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.

Thermal-diffusivity measurements by the converging-thermal-wave technique

1986 ◽  
Vol 64 (9) ◽  
pp. 1172-1177 ◽  
Author(s):  
P. Cielo ◽  
L. A. Utracki ◽  
M. Lamontagne
Keyword(s):  
Thermal Diffusivity ◽  
Thermal Wave ◽  
Infrared Detector ◽  
Thermal Flux ◽  
Thin Sheet ◽  
High Amplitude ◽  
Practical Implementation ◽  
Noise Sources ◽  
Wave Technique ◽  
Effect Of Surface

A converging-thermal-wave technique is described for the measurement of thermal diffusivity in bulk or thin-sheet materials. An annular-shaped area is heated by a pulsed laser beam focused on the material's surface through a combination of spherical and conical lenses, and the surface temperature is monitored by an infrared detector focused on the center of the annulus. The converging action of the thermal flux results in a high amplitude of the detected signal with little overheating of the irradiated material. An analysis of such a technique is presented, as well as some experimental results obtained on heterogeneous materials. Several aspects relevant to the practical implementation of such a technique in an industrial environment, such as the effect of surface losses and different noise sources, are discussed.

Fracture observation of polycrystalline diamond film under indentation test

2004 ◽  
Vol 13 (11-12) ◽  
pp. 2024-2030 ◽  
Author(s):  
R. Ikeda ◽  
M. Hayashi ◽  
A. Yonezu ◽  
T. Ogawa ◽  
M. Takemoto
Keyword(s):  
Diamond Film ◽  
Indentation Test ◽  
Polycrystalline Diamond ◽  
Polycrystalline Diamond Film

High Resolution Tem Study of Diamond Formation on Silicon and Molybdenum Field Emitter Surfaces

1994 ◽  
Vol 354 ◽  
Author(s):  
A. F. Myers ◽  
J. Liu ◽  
W. B. Choi ◽  
G. J. Wojak ◽  
J. J. Hren
Keyword(s):  
High Resolution ◽  
Diamond Film ◽  
Microwave Plasma ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Plasma Chemical Vapor Deposition ◽  
Field Emitters ◽  
High Resolution Tem ◽  
Diffraction Patterns ◽  
Polycrystalline Diamond Film

AbstractDiamond is an attractive material for coating microfabricated metal and semiconductor field emitters, since it enhances the stability and emission characteristics of the emitter. In the present study, polycrystalline diamond thin films were grown on silicon and molybdenum field emitters by microwave plasma chemical vapor deposition, using the bias-enhanced nucleation technique. High resolution transmission electron microscopy (TEM) was used to analyze the morphology of the diamond film and the structure of the diamond/emitter interface. Electron diffraction patterns and high resolution images indicate the presence of a polycrystalline diamond film, as well as a polycrystalline SiC layer between the diamond film and the Si emitter. A carbide interlayer was also found to exist between the diamond and the Mo emitter surface. Parallel electron energy loss spectroscopy confirms the TEM identification of a polycrystalline diamond film.

The Characteristics of Diamond Film Deposited by Magnet-Enhanced Plasma Jet CVD

1996 ◽  
Author(s):  
K. Zhou ◽  
M. Dair ◽  
D. Wang ◽  
P. Han ◽  
B. Feng
Keyword(s):  
Magnetic Field ◽  
Diamond Film ◽  
Polycrystalline Diamond ◽  
Plasma Jet ◽  
Magnetic Effect ◽  
X Ray Diffraction ◽  
X Ray ◽  
Crystal Perfection ◽  
Polycrystalline Diamond Film ◽  
Scanning Electron

Abstract A diameter of 30 mm polycrystalline diamond film has been deposited by magnet-enhanced DC plasma jet CVD. The diamond film was characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy and surface profilograph. Results reveal that under the same depositing parameters, magnetic field can increase purity of diamond film, improve thickness uniformity of diamond film, but no influence on crystal perfection and size of microcrystal of diamond film. A discussion on magnetic effect is presented.

Sign in / Sign up

Export Citation Format

Share Document