The crystallization behaviors, thermal stabilities, and the amorphous/crystalline structures of Calcium (Ca) doped Ge₂Sb₂Te₅ (GST) phase change films have been studied. It was found that, the thermal stability is deteriorated and two-step crystallization behavior is accelerated in GST doped with a small amount of Ca (less than 3.6 at.%), but the thermal stability is increased and two-step crystallization behavior is suppressed apparently in the more Ca-doped GST. Moreover, we found Ca does not bond with the elements of Sb and Te, implying Ca can be considered as the impurity atom in doped GST films. Together with the vacancy concept in rapid phase transition mechanism, the change of the thermal stability could be explained well in Ca-doped GST films. The Ca_6.4(GST)_93.6 film with moderate Ca doping, which has better thermal stability and faster phase transition speed in Ca-doped GST films, is suggested as a potential candidate material for phase change application.

研究了钙（Ca）掺杂的Ge ₂ Sb ₂ Te ₅（GST）相变膜的结晶行为，热稳定性和非晶/晶体结构。已经发现，在掺入少量Ca（小于3.6at。％）的GST中，热稳定性变差并且加速了两步结晶行为，但是热稳定性增加并且抑制了两步结晶行为。显然是在掺Ca的GST中。此外，我们发现Ca与Sb和Te的元素不结合，这意味着Ca可以视为掺杂GST膜中的杂质原子。结合快速相变机理中的空位概念，可以很好地解释掺Ca的GST薄膜的热稳定性变化。钙_6.4（GST）_93.6中等Ca掺杂的薄膜建议作为相变应用的潜在候选材料，该薄膜在掺Ca的GST薄膜中具有更好的热稳定性和更快的相变速度。