Crystallization kinetics of Si20Te80−xBix (0 ≤ x ≤ 3) chalcogenide glasses

Highlights: • Si₂₀Te_80−xBi_x (0 ≤ x ≤ 3) glassy alloys are synthesized using melt quenching technique. • DSC thermograms obtained under non-isothermal conditions are analyzed. • $T_g$, $T_c$, $E_g$ and $E_c$ are found to decrease with the increase of Bi. • Easy devitrifiability of the glassy alloys is useful for phase-change memory applications. -- Abstract: In this report, we investigate the crystallization kinetics of Si₂₀Te_80−xBi_x (0 ≤ x ≤ 3) chalcogenide glassy systems using differential scanning calorimetry (DSC) technique. Systematic studies are carried out in order to understand the variation of thermal parameters such as glass transition temperature ($T_g)$, onset crystallization temperature ($T_c)$ and peak crystallization temperature ($T_p)$ as a function of composition. Activation energy for glass transition ($E_g)$ and crystallization ($E_c)$ has been calculated based on the relevant statistical methods. Furthermore, thermal parameters such as change in specific heat ($\Delta C_p)$, fragility index ($F)$, thermal stability ($\Delta T$) & (S), enthalpy ($\Delta H_c)$, entropy ($\Delta S)$ are deduced to interpret distinct material behaviour as a function of composition. Structural evaluation like thermal devitrification studies elucidate the restricted glass formability of the studied glass system. Conclusively, a relationship has been established between the obtained thermal parameters and electrical switching characteristics.