The study of the electronic properties of ultrathin films
of pure bismuth and bismuth-antimony alloys is of interest, since
an increase in conductivity with decreasing sample thickness was
found. This paper presents the results of an experimental study
of the structure, electrical, galvanomagnetic and thermoelectric
properties of pure bismuth and Bi1−x Sbx thin films (x = 0.05 and
0.12) on a mica substrate in the thickness range of 10−30 nm.
An increase in the conductivity with a decrease in the thickness
of the samples was found. It may be due to the presence of
topologically protected surface states. It is shown that the features
of the manifestation of this effect are significantly influenced by the
alloys band structure. The form of the temperature dependences
of the Seebeck coefficient casts doubt on the fact that surface
states have a positive effect on the thermoelectric efficiency
of thin bismuth-antimony films. However, the detection of a
positive thermoelectric power in Bi0.88Sb0.12 samples can become
an important factor for searching for the possibility of creating a
p-branch of thermoelectric converters.