Thin Solid Films, 76(1981) 359-378
ELECTRONICS AND OPTICS 359
ELECTRICAL CONDUCTIVITY AND ELECTRON EMISSION FROM
DISCONTINUOUS METAL FILMS OF HOMOGENEOUS STRUCTURE
P. G. BORZIAK, Yu. A. KULYUPIN,S. A. NEPIJKOAND V. G. SHAMONYA
Institute of Physics, UkrainianAcademy of Sciences, Prospekt Nauki 144, Kiev 28 (U.S.S.R.)
(ReceivedAugust 4, 1980;acceptedSeptember 7, 1980)
The electrical conductivity of discontinuous metal films in weak fields is
discussed. All the structural and electrophysical characteristics of the films (the
electric field distribution, the island shape, the size distribution of islands and
interisland spacings, the field dependence of the conductivity and the influence of
temperature on the film resistivity) are investigated using a special chamber in a
transmission electron microscope with a device for electron interference. The results
obtained allow us to evaluate critically the current theories and to show the
important role of the charge effect in the conductivity of discontinuous films in a
weak field.
1. INTRODUCTION
The mechanism of electrical conductivity and associated phenomena in
discontinuous metal films has been discussed by Morris and Coutts 1. Various
practical applications of these films are to a large extent hampered by the lack of
understanding of the phenomena. Using the standard experimental devices, the
ammeter, voltmeter and thermocouple, it is possible to measure only characteristics
averaged over a large number of islands in a film and the interpretation of these can
be ambiguous. Discontinuous films constitute a complicated object of research
which can be successfully treated only by a simultaneous study of all the essential
film parameters and characteristics. In our opinion, such a comprehensive
experiment must include in situ investigations of the structure, the temperature and
field dependences of the conductivity and the electric field distribution in a film. We
have performed such investigations since 1977 and have reported some results in
refs. 2 and 3. In this paper we summarize the results on the electrical conductivity of
the films with a statistically homogeneous island structure, leaving the properties of
films with an inhomogeneous structure for a separate discussion.
2. STATEMENT OF THE PROBLEM
According to the experimental and theoretical results reported in the literature,
the key factors in understanding the electrical conductivity mechanism in
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