The crystallization mechanism and kinetics of Cr2Ge2Te6 (CrGT) films were investigated by differential scanning calorimetry. The average Avrami exponent (na) analysis indicated that CrGT exhibits a growth-dominant crystallization in the range of heating rate (β) of 102–50°C/min. In comparison, Ge2Sb2Te5 (GST) showed a nucleation-dominant crystallization. The na of CrGT was about 3, and was majorly independent of β. The na of GST decreased with an increasing p, which asymptotically approached a value of around 3. The kinetic constant of CrGT was evaluated to be almost the same with that of GST, indicating that CrGT undergoes fast crystallization.
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This work was supported by KAKENHI (grant nos. 18H02053 and 17J02967).
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Hatayama, S., Sutou, Y., Ando, D. et al. Crystallization mechanism and kinetics of Cr2Ge2Te6 phase change material. MRS Communications 8, 1167–1172 (2018). https://doi.org/10.1557/mrc.2018.176