Sb含量对GeTe-Sb相变薄膜电学性能和微观结构的影响

摘要

通过磁控溅射方法制备了不同成分的GeTe-Sb薄膜,利用电阻-温度(R-T)测试、X射线衍射(XRD)和电子显微学方法对其进行了电学性能和微观结构的表征.发现薄膜的晶化温度随着Sb含量的增加先升高后降低;XRD分析表明Sb含量的不同导致薄膜晶体结构的不同,GeTe-9.9％Sb和GeTe-21％Sb为GeTe型立方结构,GeTe-58％ Sb,GeTe-72％Sb和GeTe-81.5％ Sb呈Sb型菱方结构.在GeTe型和Sb型结构中,薄膜的晶粒尺寸都与晶化温度变化趋势相反.原位加热实验证实了Sb的加入对薄膜结晶机制产生了很大影响,GeTe-9.9％ Sb是典型的形核主导,而GeTe-72％Sb则更趋向于生长为主导的结晶机制.%By electrical resistivity measurement,X-ray diffraction techniques and advanced in situ TEM annealing techniques,the thermal stability of GeTe-Sb films with different Sb concentrations (0％,9.9％,21％,58％,72％,81.5％ Sb) and their corresponding microstructures were thoroughly investigated.The crystallization temperature shows a summit when Sb concentration approximates 58％.After crystallized,the GeTe-0％ Sb and GeTe-0％ Sb films are identified as GeTe-type cubic structure.The GeTe58％ Sb,72％ Sb and 81.5％ Sb films are Sb-type rhombohedra structure.The in-situ TEM annealing experiments show that the optimization of the properties by tuning Sb concentration is related to the corresponding crystallization behavior change,indicating a promising way for material optimization.