The Peculiar Role of the Third Element Indium in Density of Defect States of Se_(90)Ge_(10) Thin Films

摘要

The present paper reports the space charge limited conduction (SCLC) measurements in Se_(90)Ge_(10-x)ln_x (x = 2, 6) amorphous thin films. For this purpose, Ⅰ-Ⅴ measurements have been taken at different temperatures. The results show that an ohmic behavior is observed at low electric fields (E< 10~3 V/cm) while, at higher electric fields (E～10~4 V/cm), a super-ohmic behavior is observed. An analysis of the experimental data confirms the presence of space charge limited conduction (SCLC) in the present glassy materials. Density of defect states (DOS) near Fermi level is calculated by fitting the data to SCLC theory. The peculiar role of the third element Indium, as an impurity in Se_(90)Ge_(10) binary glassy alloy, is also discussed in terms of electro-negativity difference between the constituent elements.