ISSN 1063-7397, Russian Microelectronics, 2007, Vol. 36, No. 5, pp. 313–320. © Pleiades Publishing, Ltd., 2007.
Original Russian Text © Z.I. Taliashvili, L.R. Vardosanidze, L.B. Jangidze, A.N. Tavkhelidze, Jr., 2007, published in Mikroelektronika, 2007, Vol. 36, No. 5, pp. 359–367.
Nowadays, the surface treatment tools give no way
of receiving two ideally conformal surfaces, which are
required for high-current nanodevices . The purpose
of the present study is the development of the method
enabling us to create the structures with conformal sur-
The structures represented the sandwiches of the
Ti–Ag–Cu type (Fig. 1), in which the Ti and Ag
ﬁlms were obtained by vacuum deposition and the Cu
upper layer  was obtained by electrolytic coating.
The surface modiﬁcation of the required ﬁlm was car-
ried out between the processes of vacuum deposition in
order to carry out a controllable thermal splitting of
given structures at the boundary between the Ti and Ag
Conformity of the surfaces received after splitting of
the structures was evaluated optically using the Michel-
The wafers of
-type Si (100) single-crystal with
resistivity < 0.005
cm with diameters
= 50 mm,
= 40 mm, and
= 20 mm; and thicknesses 1 mm and
2 mm were used. Both sides of the wafers were treated
to the surface ﬁnish class 14; the roughness was equal
to 0.5 nm.
The technology of fabrication of the Si–Ti–Ag–Cu
structures involves the following stages:
1. Chemical cleaning of Si wafers.
1.1. Degreasing of wafers (in dimethylformamide at
= 325 K for 3 min with the following rinsing in
1.2. Refreshing (in the solution HF + H2O (1 : 25)
for 30 s, rinsing in water).
1.3. Drying in the centrifuge.
2. Plasma cleaning of vacuum chamber and wafers
(pressure 13.3 Pa for 20 min).
2.1. Cleaning in oxygen plasma.
2.2. Cleaning in argon plasma.
3. Heating of wafers before vacuum deposition of
= 473 K).
Vacuum deposition of metal ﬁlms was carried out by
both thermal and magnetron methods without depres-
Control of the Adhesion Strength of Thin Metal Films
in Multilayer Structures
Z. I. Taliashvili, L. R. Vardosanidze, L. B. Jangidze, and A. N. Tavkhelidze, Jr.
Dzhavakhishvili State University of Tbilisi, pr. Chavchavadze 3, Tbilisi, 380028 Georgia
Received June 21, 2006
—Technology of the fabrication of multilayer structures with controllable adhesion interaction
between metal ﬁlms composing these structures is considered. Control of adhesion interaction was attained by
modifying the surface of corresponding metal ﬁlm until an adhesion bond appeared in vacuum and by changing
technological parameters. The adhesion strength was evaluated by the temperature of structure splitting due to the
difference in the coefﬁcients of thermal expansion of the substrate and ultimate metal electrode. The analysis of
surfaces prior to and after structure splitting was carried out optically using the Michelson interferometer.
PACS numbers: 68.35.Np
Experimental structure Si–Ti–Ag–Cu ((
2) Ti, (
) modiﬁed surface,