Influence of the growth parameters on the electrical properties of thin polycrystalline CVD diamond films

ABSTRACTCVD diamond films prepared under varying conditions have been investigated with IR and Raman spectroscopy. Raman spectroscopy was used to characterize the crystal structure, and ir absorption was used to determine the H bonding environments. The growth temperatures were varied in one series, while the CH4/H2 ratio was varied in another. The IR absorption of all the samples showed a weak broad band extending from approximately 2800 to 2970 cm−1 which was attributed to H bonded to sp3 C sites. There was no evidence of ir absorption at 3000 to 3200 cm−1 which would indicate H bonded to sp2 or sp1 C sites. For both series, the Raman measurements showed progression from diamond-like films to diamond films. The ir absorption showed a general trend of less H with more well ordered diamond structures. No sharp transition of the H incorporation vs the growth parameters was observed.

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Electrical Properties in Cvd Diamond Films

MRS Proceedings ◽

10.1557/proc-302-257 ◽

1993 ◽

Vol 302 ◽

Cited By ~ 3

Author(s):

S. Zhao ◽

K.K. Gan ◽

H. Kagan ◽

R. Kass ◽

R. Malchow ◽

...

Keyword(s):

Electrical Properties ◽

Carrier Mobility ◽

Average Distance ◽

Diamond Films ◽

Chemical Vapor ◽

Cvd Diamond ◽

Time Resolved ◽

Chemical Vapor Deposited ◽

Natural Type ◽

Cvd Diamond Film

ABSTRACTThe electrical properties associated with carrier mobility, μ, and lifetime, τ, have been investigated for the chemical vapor deposited (CVD) diamond films using charged particle-induced conductivity and time resolved transient photo-induced conductivity. The collection distance, d, the average distance which electron and hole depart when driven by an applied electric field E, was measured by both methods. The collection distance is related to the carrier mobility and lifetime by d = μEτ Our measurements show that the collection distance increases linearly with sample thickness for CVD diamond films. The collection distance at the growth side of the CVD diamond film is comparable to that of single crystal natural type IIa diamond; at the substrate side of the film, the collection distance is near zero. No saturation of the collection distance is observed for film thickness up to 500 microns.

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785 nm Raman Spectroscopy of CVD Diamond Films

MRS Proceedings ◽

10.1557/proc-1039-p15-02 ◽

2007 ◽

Vol 1039 ◽

Cited By ~ 1

Author(s):

Paul William May ◽

James A Smith ◽

Keith N Rosser

Keyword(s):

Raman Spectroscopy ◽

Film Thickness ◽

Raman Spectra ◽

Relative Intensity ◽

Near Infrared ◽

Diamond Films ◽

Polycrystalline Diamond ◽

Cvd Diamond ◽

Raman Study ◽

Thin Polycrystalline

AbstractRaman spectroscopy is a powerful technique often used to study CVD diamond films, however, very little work has been reported for the Raman study of CVD diamond films using near infrared (785 nm) excitation. Here, we report that when using 785 nm excitation, the Raman spectra from thin polycrystalline diamond films exhibit a multitude of peaks (over 30) ranging from 400-3000 cm−1. These features are too sharp to be photoluminescence, and are a function of film thickness. For films >30 μm thick, freestanding films, and for films grown in diamond substrates the Raman peaks disappear, suggesting that the laser is probing the disordered small-grained interface between the diamond and substrate. Some of the peaks change in relative intensity with time (‘blinking’), and the spectra are very sensitive to position on the substrate – this is reminiscent of the behaviour seen in SERS spectra.

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