Thermal stability and crystallization kinetics of Sb doped InSe alloys for phase change memory applications

Abstract

Bulk samples of In_0.1Se_0.9-xSb_x (0 ≤ x ≤ 0.24) were synthesized using the conventional melt-quenching technique. In this study, the effect of Sb doping and heating rates on thermal parameters such as glass transition temperature (T_g​), peak crystallization temperature (T_p​), and melting temperature (T_m​) were analyzed via non-isothermal differential scanning calorimetry (DSC). Various thermal stability parameters such as ΔT, K_gl, H, S and T_rg were calculated using these characteristic temperatures. Among all the studied samples, x = 0.04 exhibited the highest thermal stability, as indicated by the largest ΔT and thermal stability factors (H and S). Glass transition (E_g) and crystallization activation energies (E_c) were calculated using multiple approaches, revealing that x = 0.24 had the lowest glass transition activation energy, suggesting higher atomic mobility. The crystallization kinetics was studied using Kissinger, Mahadevan, Augis & Bennett and Matusita approaches. Crystallization activation energy (E_c) is a critical parameter for phase-change memory (PCM) applications. The calculated values of E_c suggested that x = 0.04, with the highest E_c​, is well-suited for long-term data storage. Furthermore, Avrami index and growth dimension analyses showed one-dimensional crystallization for most compositions, with exceptions for x = 0 and x = 0.04 (three-dimensional). These findings highlight the tunable thermal and crystallization properties of Sb-doped InSe alloys, making them promising candidates for PCM and multilevel memory applications.