Russian Journal of Applied Chemistry, 2012, Vol. 85, No. 5, pp. 742−746.
Pleiades Publishing, Ltd., 2012.
Original Russian Text © V.S. Protopopova, S.E. Alexandrov, 2012, published in Zhurnal Prikladnoi Khimii, 2012, Vol. 85, No. 5, pp. 741−745.
OF SYSTEMS AND PROCESSES
Kinetic Regularities of the Chemical Vapor Deposition of Nickel
Layers from Bis-(Ethylcyclopentadienyl)nickel
V. S. Protopopova and S. E. Alexandrov
St. Petersburg State Polytechnical University, St. Petersburg, Russia
Received April 6, 2012
Abstract—Physicochemical regularities of the nickel layers chemical vapor deposition from bis-
(ethylcyclopentadienyl)nickel were studied. Dependences of the growth rate of nickel layers on the deposition
temperature, gas-ﬂ ow linear rate, partial pressures of reagents, and substrate roughness, and also dependences of
the thickness of a grown layer on time and on the position of a substrate on a susceptor were obtained.
One of promising directions of using nickel thin layers
is their application as catalytic layers for the synthesis of
carbon nanostructures, nanotubes  and graphenes ,
and also as active magnetic layers  in various micro-
The method of chemical vapor deposition (CVD) al-
lows obtaining high-quality coats on large surface areas
and on products with complicated geometrical shapes,
including micro- and nanoporous surfaces. Organometal-
lic compounds are widely used as precursors in CVD pro-
cesses owing to their high volatility and low decomposi-
tion temperatures. In particular, carbonyls, β-diketonates,
acetylacetonates, and bis-π-cyclopentdienyl compounds
are used for obtaining nickel layers [4–8]. Traditionally
the deposition of metal layers is carried out in the pres-
ence of hydrogen [6, 7], as an addition of Н
the degree of uncontrollable alloying resulting layers by
A principal possibility of using bis-(ethylcyclo-
Ni] as a promising precursor
for obtaining nickel layers was shown in . The aim
of the present work was the study of physicochemical
regularities of the process including the determination
of the limiting stage type.
Nickel layers were deposited in a technological instal-
lation equipped by a horizontal reactor with “hot walls”
intended for realization of CVD processes under reduced
pressure. The installation is described in detail in .
The experimental study of the nickel layers deposition
was carried out in the temperature range 665–925 K at the
following gas-phase parameters: partial pressure of bis-
(ethylcyclopentadienyl)nickel, from 8 up to 100 Pa, that
of hydrogen, from 0 up to 350 Pa, a ﬂ ow of argon used as
a gas-carrier through the evaporator, 50 cm
gas ﬂ ow 100 cm
, and total pressure 840 Pa. Typical
deposition time was 60 min. As substrates we used n-type
silicon wafers (111) and (100) with a speciﬁ c electrical
resistivity of 7.5 Oh cm, and polycrystalline Nb foil.
The results of preliminary experiments point to an es-
sential decrease in the thickness of layers in the direction
from the centre to the edges of a substrate (Fig. 1), which
probably is connected with a concentration gradient of
the precursor in a reactor. In this connection we have
chosen a ﬁ eld in a center of susceptor for the arrangement
of substrates, where the thickness of layers was constant
to within ±10%.
To determine the thickness of resulting Ni layers, we
have developed a technique based on measuring inten-
sity of a characteristic line of the element in the X-ray
ﬂ uorescence (XRF) analysis. The technique was realized
on a “Spectroscan MAX-GV” XFR spectrometer. The
spectrometer was graduated by standard samples. The