Investigation of switching phenomenon of Se₇₅Te _25-xGa_x amorphous system

Thin film samples of different thicknesses ranging from 185 to 630 nm, were prepared from the synthesized amorphous Se₇₅Te_25-xGa _x (0 ≤ x ≤ 15 at.%) chalcogenide glass compositions by thermal evaporation technique. X-ray analysis showed that the amorphous nature of the obtained films. Investigations of the current-voltage (I-V) characteristics of amorphous films are typical for a memory type switch. The conduction activation energy (ΔE_σ) was calculated from the temperature dependence of the sample resistance of the studied films in the temperature range (293-333 K) below the glass transition temperature. The mean value of the threshold switching voltage V̄_th increases linearly with increasing film thickness and decreases exponentially with temperature (below T_g) for all investigated compositions. The threshold voltage activation energy ε_th was calculated from the temperature dependence of V̄_th of the studied films. The switching phenomenon observed in these films is explained in accordance with the electrothermal model for the switching process. The effect of Ga content on the studied parameters was also investigated.