A composition-dependent thermal behavior of Si20Te80−xSnx glasses: Observation of Boolchand intermediate phase

Thermal properties have been investigated using alternating differential scanning calorimetry (ADSC) for determining the phase transitions of Si ₂₀Te _80−xSn _x glass samples (1 ≤ x ≤ 6). Experiments are performed to assess the variations of thermal characteristics such as glass transition temperature (T _g) and crystallization temperature (T _c) etc. as a function of Sn variation. The glass-forming ability (GFA) and thermal stability (ΔT) are analyzed for understanding the suitability of as-prepared material in terms of network connectivity and rigidity. The studies have revealed minimum non-reversing enthalpy (ΔH _NR) value between compositions (2 ≤ x ≤ 5) of Si ₂₀Te _80−xSn _x glasses, which serve as a basis of the existence of Boolchand`s intermediate phase (BIP). It is observed that an increase in Sn dopant resulted in an increase in the density and decrease in the molecular volume of Si ₂₀Te _80−xSn _x samples. These studies reveal the correlation with the memory switching behavior displayed by Si ₂₀Te _80−xSn _x glasses.