The complex dielectric constant frequency spectra of vaporhyphen;deposited amorphous Sesngbnd;Bi and Sesngbnd;Bisngbnd;As films were measured as a function of heat treatment near the glass transition temperature. The observed dielectric dispersions have been attributed to interfacial polarization arising from a layering of alternate highhyphen;bismuth and lowhyphen;bismuth amorphous phases parallel to the surface of the film. Theoretical equations based on this interfacial polarization model have been used to reproduce the observed dielectric behavior. The model can correctly fit the observed loss peak frequencies and amplitudes and the increase of the peak frequencies with increasing time of heat treatment for lowerhyphen;bismuthhyphen;concentration films (5.0 at.percnt; Bi). At higher bismuth concentrations conducting paths must be proposed in order to account for the very large dispersion peaks and lowhyphen;frequency dielectric constants which are observed. These paths occur either through individual highhyphen;bismuth layers or through the bulk of the film. The addition of arsenic to the lowhyphen;bismuthhyphen;concentration films increases the overhyphen;all conductivity and causes a conductivity maximum with heat treatment in the highhyphen;conductivity layers. In the highhyphen;bismuthhyphen;concentration films the arsenic tended to stabilize the amorphous phases of the film.
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