Deposition of amorphous carbon layers from C2H2 and CF4 with an expanding thermal arc plasma beam set-up

Kleuskens

Journal of Applied Physics

et al. 1996

Amorphous hydrogenated carbon films have been deposited on crystalline silicon and on glass from an expanding thermal plasma. Two deposition parameters have been varied: the electric current through the plasma source and the admixed acetylene flow. No energetic ion bombardment has been applied during deposition. Ex situ analysis of the films yields the infrared refractive index, hardness, Young's modulus, optical band gap, bonded hydrogen content, and the total hydrogen and mass density. The infrared refractive index describes the film properties independent of which plasma deposition parameter ͑arc current or acetylene flow͒ has been varied. The hardness, Young's modulus, sp 2 /sp 3 ratio, and mass density increase with increasing refractive index. The optical band gap and hydrogen content of the films decrease with increasing refractive index. It is demonstrated that plasma-beam-deposited diamondlike a-C:H has similar properties as material deposited with conventional plasma-enhanced chemical-vapor-depositions techniques under energetic ion bombardment.

Section: Film Analysismentioning

confidence: 99%

Section: Film Analysismentioning

confidence: 99%

See 1 more Smart Citation

Optical and mechanical properties of plasma-beam-deposited amorphous hydrogenated carbon

Kleuskens

Journal of Applied Physics

et al. 1996

“…In the past, this technique has been applied successfully for the deposition of diamond, graphite, amorphous hydrogenated silicon, and amorphous ͑fluoro͒hydrogenated carbon. 5,6 The deposition setup consists of a dc plasma arc, a vacuum chamber, and a substrate holder. The arc 4 generates a subatmospheric thermal plasma in argon ͑argon flow: 100 scc/s, electron density: Ϸ10 22 m…”

Section: ͓S0003-6951͑96͒02228-0͔mentioning

confidence: 99%

Plasma beam deposited amorphous hydrogenated carbon: Improved film quality at higher growth rate

Applied Physics Letters

Schram

1996

High quality diamondlike a-C:H has been deposited, at low ion bombardment energies, from an expanding thermal argon/acetylene plasma at high growth rate. It is observed that quality improvement, in terms of hardness, is equivalent to maximization of the refractive index. The highest refractive indices are obtained when the admixed acetylene flow and the argon ion flux emanating from the plasma source are comparable in magnitude, which suggests critical loading. This also indicates that the acetylene has to be dissociated only once. Combination with the observed quality behavior at higher deposition rates suggests that there is one preferred hydrocarbon radical for deposition, probably C2H.

“…With this technique carbon films have been deposited, varying from amorphous hydrogenated films [7] to graphite [8], diamond [9] and fluorohydrogenated films [10,11].…”

Section: Introductionmentioning

confidence: 99%

Quality improvement of plasma-beam-deposited amorphous hydrogenated carbon with higher growth rate

Plasma Sources Sci. Technol.

Kleuskens

et al. 1996

An improved plasma beam deposition set-up, based on an expanding thermal plasma, is presented. Amorphous hydrogenated carbon films have been deposited on glass and crystalline silicon, under variation of the arc current and admixed acetylene flow. The films have been analysed ex situ with infrared absorption spectroscopy, broadband visible light transmission and nano-indentation measurements. These techniques reveal the growth rate, refractive index, bonded C-H density, optical bandgap and hardness. The growth rate and refractive index are found to increase with decreasing arc current and increasing acetylene flow admixture. The quality of the films in terms of refractive index and hardness increases with increasing growth rate and inverse energy coefficient, whereas the bonded hydrogen concentration and optical bandgap then decrease. From comparison of the growth rate dependency with the inverse energy coefficient dependency, we conclude that the growth rate is the preferred parameter in terms of which to describe the film properties because it is directly related to the plasma composition.