Space charge limited conduction in bulk Se100 − xSbx chalcogenide glasses

The present paper reports the measurements on space charge limited conduction in bulk glassy Se100 − xSbx (x = 2, 4, 6, 8). I–V characteristics have been measured at various fixed temperatures. These characteristics show that, at low electric fields, an ohmic behaviour is observed. However, at high electric fields (E ∼104 V/cm), the current becomes superohmic.At high fields (104 V/cm), current could be fitted to the theory of space charge limited conduction in case of uniform distribution of localized states in the mobility gap of these materials. Using the theory of SCLC for the uniform distribution of the traps, the density of localized states near Fermi level is also calculated. Density of localized states initially increases with Sb concentration till 6 at.% of Sb and then decreases with further increase of Sb. This decrease is explained in terms of average coordination number.