ISSN 10637397, Russian Microelectronics, 2014, Vol. 43, No. 8, pp. 587–589. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © I.S. Smirnov, E.G. Novoselova, A.A. Egorov, I.S. Monakhov, 2013, published in Izvestiya Vysshikh Uchebnykh Zavedenii. Materialy Elektronnoi Tekhniki,
2013, No. 1, pp. 35–37.
Today the production of the optics and microelec
tronics items requires forming onelayer and multi
layer compositions with different functions on dielec
tric, semiconductor, and metal substrates. The exam
ples of such structures can be optic interference
claddings, mirrors of a soft Xray range, and semicon
ductor superlattices. The peculiarity of modern elec
tronics lies in the use of progressively thinner layers
and the transition from the microdimensional to the
nanodimensional films. The application of such clad
dings makes increased demands on the quality of the
substrate cladding, the state of the borders between the
layers, and the homogeneity of separate layers. The
surface state can be experimentally estimated by vari
ous physical (optic and probe) methods, each of which
has its own advantages and application area. The mon
itoring methods allowing one to measure the film
structure parameters directly during their formation,
namely, the in situ methods, have gained great signifi
cance. They provide obtaining films with the given
parameters, allowing one to correct the technological
In the past ten years, many investigations on the
growth and ion etching of thin films using different
methods were carried out. However, the studied pro
cess breaks in most of them. The samples are tested in
air. Clearly, such an approach has some disadvantages.
(1) Oxidation of the surface often leads to the
increased roughness in comparison with the one
formed immediately after deposition.
(2) Interaction between the surface and air leads to
a change in the nearsurface layer, including the for
mation of the oxide and adhesion layers.
(3) Artifacts can appear upon investigating the
samples (e.g., films that are different in thickness films
coated on identical substrates).
(4) Research work without a camera after termina
tion of the technological process (ex situ ) often does
not provide an exact determination of the temporary
evolution of the sample parameters with respect to the
technological parameters, e.g., annealing time.
Below we give the studied possibilities of the in situ
method of the Xray reflectometry for defining nan
odimensional films in real time.
In the simple variant, the in situ
try can be implemented based on the analysis of the
temporary dependence between the intensity of the
specularly reflected Xray beam from the sample,
which is recorded at the fixed sliding angle
. As a
result of changing the phase difference in the waves
reflected by the growing film and substrate surfaces,
the interference image represents the oscillations of
the Xray radiation intensity . To implement the
method, a vacuum technological complex, including a
vacuum camera, deposition node, and measuring
Xray reflectory system, was generated.
In practice, the rate at ehich the films are formed
generally lies in the range from tenths of a fraction to
units of nanometers per second. This constrains the
data processing time and requires simplifying the cal
culation algorithm. In the general case, the coefficient
of the reflection from the system, the film–substrate is
described by recurrent expressions . Recording the
time dependence of the reflection coefficient
Applying the In Situ XRay Reflectometry Method to Define
the Nanodimensional Silicon Film Parameters
I. S. Smirnov
, E. G. Novoselova
, A. A. Egorov
, and I. S. Monakhov
Moscow Institute of Electronics and Mathematics (Technical University), bol. Trekhsvjatitel’skij per. 13/12, Moscow, Russia
Federal BudgetFunded Research Institute of Advanced Materials and Technologies, Russia
—The monitoring methods for measuring the film structure parameters in formation process,
namely, the in situ methods, are currently of special significance. Their application provides obtaining the
films with the given characteristics, which results in a fast correction of the technological modes. The possi
bilities of the in situ method of the Xray reflectometry for defining the parameters of the nanodimensional
films during their formation are discussed. The results are given of testing the magnetron deposition of the
silicon films and other materials on the silicon substrate.
silicon, magnetron deposition, Xray reflectometry