The amorphous carbon films were deposited on silicon-metal substrates by plasma jet chemical vapor
deposition (PJCVD) and plasma enchanted CVD (PECVD). PJCVD carbon coatings have been prepared at
atmospheric pressure in Ar/ C2H2 and Ar/H2/C2H2 mixtures. The films prepared in Ar/C2H2 plasma are attributed
to graphite-like carbon films. Addition of the hydrogen decreases growth rate and the surface
roughness of the coatings, but coatings have low fraction of oxygen (~5 at.%) The formation of the nanocrystalline
graphite was obtained in Ar/H2/C2H2 plasma. The carbon nanotubes were synthesed by PECVD
using Au/Cr catalyst particles at low (≤ 450 C; p = 40 Pa ) temperature in pure acetylene.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3538

Carnauskas, M.

Grigonis, A.

Kaliasas, R.

Marcinauskas, L.

SocioEconomic Challenges Journal (Sumy State University)

PROCEEDINGS OF THE INTERNATIONAL CONFERENCE NANOMATERIALS: APPLICATIONS AND PROPERTIES 
Vol. 1 No 4, 04PITSE02(2pp) (2012) 
 
 
2304-1862/2012/1(1)04PITSE02(2) 04PITSE02-1  2012 Sumy State University 
Graphite Nanostructures Produce in the Acetylene, Argon-Acetylene  
and Argon-Hydrogen-Acetylene Plasmas  
 
L. Marcinauskas1,2,*, M. Černauskas1 R. Kaliasas1, A. Grigonis1,†  
 
1 Kaunas University of Technology, Studentu 50, LT-51368, Kaunas, Lithuania 
2 Lithuanian Energy Institute, Breslaujos 3, LT-44403, Kaunas, Lithuania  
 
(Received 11 July; published online 12 July 2012) 
 
The amorphous carbon films were deposited on silicon-metal substrates by plasma jet chemical vapor 
deposition (PJCVD) and plasma enchanted CVD (PECVD). PJCVD carbon coatings have been prepared at 
atmospheric pressure in Ar/ C2H2 and Ar/H2/C2H2 mixtures. The films prepared in Ar/C2H2 plasma are at-
tributed to graphite-like carbon films.  Addition of the hydrogen decreases growth rate and the surface 
roughness of the coatings, but coatings have low fraction of oxygen (~5 at.%) The formation of the nano-
crystalline graphite was obtained in Ar/H2/C2H2 plasma. The carbon nanotubes were synthesed by PECVD 
using Au/Cr catalyst particles at low (≤ 450  C; p = 40 Pa ) temperature in pure acetylene. 
 
Keywords: Graphite nanostructures, Acetylene, Plasma. 
 
  PACS numbers: 52.77. – j, 81.05.U –  
 
 
                                                          
* liutauras.marcinauskas@ktu.lt 
† alfonsas.grigonis@ktu.lt 
1. INTRODUCTION 
 
Carbon nanostructures (nanotubes, nanoonions, car-
bon black, fullerene and etc.) have received considerable 
attention due to their unique mechanical, optical, electri-
cal and electronic properties. These fascinating proper-
ties make the carbon nanostructures great candidates 
for application in a wide variety of fields [1, 2].  
Various deposition techniques are used to produce 
graphite nanostructures. It was shown that the synthe-
sis temperature and characteristics of the catalyst play 
a key role in controlling the structure of carbon 
nanostructures [1-3]. 
In this paper graphite nanostructures were fabri-
cated from acetylene gas at 40 Pa and at atmospheric 
pressures. Experimental work was done to investigate 
the effect of various acetylene gas flow and tempera-
tures on the graphite structure formation. 
 
2. EXPERIMENTAL SETUP 
 
The amorphous carbon films were deposited on Si-
metal substrates by plasma PJCVD and PECVD. 
PJCVD carbon coatings have been prepared at atmos-
pheric pressure in Ar/C2H2 and Ar/H2/C2H2. Ar (flow 
rate of 6.6 l/min) and H2 (flow rates of 0.06÷0.24 l/min) 
were used as feed gases, and C2H2 (0.066 l/min or 0.044 
l/min) as a precursor [4]. The distance between plasma 
torch nozzle exit and the samples was 0.005 m.  
PECVD carbon films have been prepared at ~ 40 Pa 
pressure in pure acetylene. Carbon nano-structures, as 
a function of substrate temperature and plasma activa-
tion of reactive species using catalyst particles forming 
with electron beam lithography, laser radiation and 
thermal annealing methods. 
 Surface morphology was characterized by SEM, el-
emental composition of formed thin films determinate 
by energy-dispersive spectrometry (EDS). Bonding 
structure and optical properties were determined by 
Fourier transform infrared (FTIR) and Raman scatter-
ing spectroscopy. RS was investigated using Spectra – 
Physics YAG: Nd laser (532.3 nm, 50 mW, spot size 
0.32 mm). 
 
3. RESULTS AND DISCUSIONS  
 
The coatings deposited from argon-acetylene plas-
ma are rough and consist of columnar structure (Fig. 
1). The films growth rate decreased, oxygen concentra-
tion and sp2 sites fraction increased with decreasing 
C2H2 flow rate. The surface roughness and growth rate 
of the graphite films decreases with introduction of the 
hydrogen and with the increase of H2 flow rate.  
 
  
 
Fig. 1 – Surface morphology of structures formed in Ar/C2H2 
plasma 
 
The EDS measurement indicated that coatings pre-
pared without the H2 have low fraction of oxygen (~5 
at.%), meanwhile the addition of hydrogen increase 
oxygen fraction up to ~10 at.%. 
The films prepared in Ar/C2H2 plasma at high tem-
perature (800-1200 oC) are attributed to graphite-like 
carbon films with significant fraction of sp3 C-C sites. 
The synthesis of the nanocrystalline graphite was ob-
 L. MARCINAUSKAS, M. CERNAUSKAS, R. KALIASAS, A. GRIGONIS PROC. NAP 1, 04PITSE02 (2012) 
 
 
04PITSE02-2 
tained in Ar/H2/C2H2 plasma. The formation of carbon 
nanostructures of 1-2 μm length and up to 200 nm di-
ameters were obtained using argon-hydrogen-acetylene 
plasma on Si-Ni and Si-Au substrates (Fig. 2). The var-
iation of the technological parameters allows changing 
the IR reflectance values of carbon films in wide range. 
 
 
 
Fig. 2 – Surface morphology of structures formed using 
Ar/H2/C2H2 plasma 
It was found that the formation of the carbon nano-
tubes begins on the Si substrate covered by Au/Cr 
nano-islands (forming with electron beam lithogra-
phy and laser radiation methods ) in pure acetylene 
gas plasma at ~ 450 C temperatures. 
 
4. CONLUSIONS 
 
The films prepared in Ar/C2H2 plasma are attribut-
ed to graphite-like carbon films.  Addition of the hydro-
gen decreases growth rate and the surface roughness of 
the coatings and lead to formation of nanocrystalline 
graphite. The carbon nanotubes were formed at low  
(≤ 450 C; p = 40 Pa) temperature in pure acetylene. 
 
AKNOWLEDGEMENTS 
 
This research was partly funded by a grant (No. 
MIP-59/2010) from the Research Council of Lithuania. 
The authors also thank D. Milčius from the Lithuanian 
Energy Institute for possibility to perform SEM and 
EDS measurements. 
 
 
REFERENCES 
 
1. J. Robertson, Mater. Sci. Eng. B 37, 129 (2002).  
2. J. Gonzalez-Aguilar, M. Morena, L. Fulcheri, J. Phys. D: 
Appl. Phys. 40, 2361 (2007). 
3. C.C. Chuang et al. Appl. Surf. Science 254, 4681 (2008).  
4. L. Marcinauskas, A. Grigonis, V. Valinčius, J. Non-Cryst. 
Solids 355, 1240 (2009). 
 
 


English

Graphite Nanostructures Produce in the Acetylene, Argon-Acetylene and Argon-Hydrogen-Acetylene Plasmas

Electronic Sumy State University Institutional Repository

PROCEEDINGS OF THE INTERNATIONAL CONFERENCE NANOMATERIALS: APPLICATIONS AND PROPERTIES Vol. 1 No 4, 04PITSE02(2pp) (2012)   2304-1862/2012/1(1)04PITSE02(2) 04PITSE02-1  2012 Sumy State University Graphite Nanostructures Produce in the Acetylene, Argon-Acetylene  and Argon-Hydrogen-Acetylene Plasmas   L. Marcinauskas1,2,*, M. Černauskas1 R. Kaliasas1, A. Grigonis1,†   1 Kaunas University of Technology, Studentu 50, LT-51368, Kaunas, Lithuania 2 Lithuanian Energy Institute, Breslaujos 3, LT-44403, Kaunas, Lithuania   (Received 11 July; published online 12 July 2012)  The amorphous carbon films were deposited on silicon-metal substrates by plasma jet chemical vapor deposition (PJCVD) and plasma enchanted CVD (PECVD). PJCVD carbon coatings have been prepared at atmospheric pressure in Ar/ C2H2 and Ar/H2/C2H2 mixtures. The films prepared in Ar/C2H2 plasma are at-tributed to graphite-like carbon films.  Addition of the hydrogen decreases growth rate and the surface roughness of the coatings, but coatings have low fraction of oxygen (~5 at.%) The formation of the nano-crystalline graphite was obtained in Ar/H2/C2H2 plasma. The carbon nanotubes were synthesed by PECVD using Au/Cr catalyst particles at low (≤ 450  C; p = 40 Pa ) temperature in pure acetylene.  Keywords: Graphite nanostructures, Acetylene, Plasma.    PACS numbers: 52.77. – j, 81.05.U –                                                              * liutauras.marcinauskas@ktu.lt † alfonsas.grigonis@ktu.lt 1. INTRODUCTION  Carbon nanostructures (nanotubes, nanoonions, car-bon black, fullerene and etc.) have received considerable attention due to their unique mechanical, optical, electri-cal and electronic properties. These fascinating proper-ties make the carbon nanostructures great candidates for application in a wide variety of fields [1, 2].  Various deposition techniques are used to produce graphite nanostructures. It was shown that the synthe-sis temperature and characteristics of the catalyst play a key role in controlling the structure of carbon nanostructures [1-3]. In this paper graphite nanostructures were fabri-cated from acetylene gas at 40 Pa and at atmospheric pressures. Experimental work was done to investigate the effect of various acetylene gas flow and tempera-tures on the graphite structure formation.  2. EXPERIMENTAL SETUP  The amorphous carbon films were deposited on Si-metal substrates by plasma PJCVD and PECVD. PJCVD carbon coatings have been prepared at atmos-pheric pressure in Ar/C2H2 and Ar/H2/C2H2. Ar (ﬂow rate of 6.6 l/min) and H2 (flow rates of 0.06÷0.24 l/min) were used as feed gases, and C2H2 (0.066 l/min or 0.044 l/min) as a precursor [4]. The distance between plasma torch nozzle exit and the samples was 0.005 m.  PECVD carbon films have been prepared at ~ 40 Pa pressure in pure acetylene. Carbon nano-structures, as a function of substrate temperature and plasma activa-tion of reactive species using catalyst particles forming with electron beam lithography, laser radiation and thermal annealing methods.  Surface morphology was characterized by SEM, el-emental composition of formed thin films determinate by energy-dispersive spectrometry (EDS). Bonding structure and optical properties were determined by Fourier transform infrared (FTIR) and Raman scatter-ing spectroscopy. RS was investigated using Spectra – Physics YAG: Nd laser (532.3 nm, 50 mW, spot size 0.32 mm).  3. RESULTS AND DISCUSIONS   The coatings deposited from argon-acetylene plas-ma are rough and consist of columnar structure (Fig. 1). The films growth rate decreased, oxygen concentra-tion and sp2 sites fraction increased with decreasing C2H2 flow rate. The surface roughness and growth rate of the graphite films decreases with introduction of the hydrogen and with the increase of H2 flow rate.      Fig. 1 – Surface morphology of structures formed in Ar/C2H2 plasma  The EDS measurement indicated that coatings pre-pared without the H2 have low fraction of oxygen (~5 at.%), meanwhile the addition of hydrogen increase oxygen fraction up to ~10 at.%. The films prepared in Ar/C2H2 plasma at high tem-perature (800-1200 oC) are attributed to graphite-like carbon films with significant fraction of sp3 C-C sites. The synthesis of the nanocrystalline graphite was ob- L. MARCINAUSKAS, M. CERNAUSKAS, R. KALIASAS, A. GRIGONIS PROC. NAP 1, 04PITSE02 (2012)   04PITSE02-2 tained in Ar/H2/C2H2 plasma. The formation of carbon nanostructures of 1-2 μm length and up to 200 nm di-ameters were obtained using argon-hydrogen-acetylene plasma on Si-Ni and Si-Au substrates (Fig. 2). The var-iation of the technological parameters allows changing the IR reflectance values of carbon films in wide range.    Fig. 2 – Surface morphology of structures formed using Ar/H2/C2H2 plasma It was found that the formation of the carbon nano-tubes begins on the Si substrate covered by Au/Cr nano-islands (forming with electron beam lithogra-phy and laser radiation methods ) in pure acetylene gas plasma at ~ 450 C temperatures.  4. CONLUSIONS  The films prepared in Ar/C2H2 plasma are attribut-ed to graphite-like carbon films.  Addition of the hydro-gen decreases growth rate and the surface roughness of the coatings and lead to formation of nanocrystalline graphite. The carbon nanotubes were formed at low  (≤ 450 C; p = 40 Pa) temperature in pure acetylene.  AKNOWLEDGEMENTS  This research was partly funded by a grant (No. MIP-59/2010) from the Research Council of Lithuania. The authors also thank D. Milčius from the Lithuanian Energy Institute for possibility to perform SEM and EDS measurements.   REFERENCES  1. J. Robertson, Mater. Sci. Eng. B 37, 129 (2002).  2. J. Gonzalez-Aguilar, M. Morena, L. Fulcheri, J. Phys. D: Appl. Phys. 40, 2361 (2007). 3. C.C. Chuang et al. Appl. Surf. Science 254, 4681 (2008).  4. L. Marcinauskas, A. Grigonis, V. Valinčius, J. Non-Cryst. Solids 355, 1240 (2009).   

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Graphite Nanostructures Produce in the Acetylene, Argon-Acetylene and Argon-Hydrogen-Acetylene Plasmas

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