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

Abstract

Bulk samples of In0.1Se0.9-xSbx (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 (Tg​), peak crystallization temperature (Tp​), and melting temperature (Tm​) were analyzed via non-isothermal differential scanning calorimetry (DSC). Various thermal stability parameters such as ΔT, Kgl, H, S and Trg 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 (Eg) and crystallization activation energies (Ec) 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 (Ec) is a critical parameter for phase-change memory (PCM) applications. The calculated values of Ec suggested that x = 0.04, with the highest Ec​, 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.