A comparative study of dielectric properties of As/sub 2/Se/sub 3/ and As/sub 2/Se/sub 3/Bi/sub x/ glassy systems

Abstract

We report about the peculiarities of the dielectric properties of a-As/sub 2/Se/sub 3/ and As/sub 2/Se/sub 3/Bi/sub x/ (x=20 at.%) layers. The As/sub 2/Se/sub 3/ layers are characterized by gradual decrease of /spl epsiv/ with frequency and increase with temperature. A broad maximum is registered on tg/spl delta/-f dependence. At low frequencies f<10/sup -1/ Hz the loss factor increases with temperature. For modified system As/sub 2/Se/sub 3/Bi/sub x/ much greater decrease of /spl epsi/ with frequency and increase with temperature is found. tg/spl delta/-f dependence of this system demonstrates no maximum and at frequencies f<10/sup -1/ Hz the loss factor decreases with temperature. The mentioned above results confirm the assumption that the metal dopants act as positively charge impurities.