Kinetic properties of bismuth thin films
Abstract
A study was made of the temperature variation (in the 1.5–300°K range) of the resistance, magnetoresistance and Hall coefficient of epitaxial bismuth films of thickness 170–5000 Ǻ. A number of peculiarities and anomalies in the behavior of the kinetic properties were observed and studied: the complex character of the temperature variation of the parameters found, the presence of an initial quadratic section in the dependences of the variation of the resistance in a magnetic field with extremely high values of the magnetoresistance coefficient, the appearance of an anomalous dimensional effect in the conductivity, etc. By means of calculations using the equations for a two-band model of semimetals the temperature and “thickness” variations of the carrier concentration and mobility were distinguished. The results obtained could be explained by invoking the theory of resonance scattering of carriers in size-quantized films and a model of potential distortion close to the film surface.