近年來，碳中和相關的議題備受矚目，全球致力於減少碳排放量，因此再生能源相關的研究逐漸增加，熱電裝置即是一種能將熱能與電能交互轉換的技術，若能將廢熱轉換成可用的電能，將能進一步提升能源使用效率。熱電材料模組化後，由於嚴重的交互擴散以及界面反應導致模組的熱電性質大幅下降，正確選擇熱電薄膜的電極材料與擴散阻障層材料可提升整體的功率因子。本研究將Cu/Sb2Te3/Cu、Ni/Sb2Te3/Ni、Cu/Co/Sb2Te3/Co/Cu模組進行長時間時效熱處理，模擬實際應用下，熱電性質與薄膜組成的變化，在Cu/Sb2Te3/Cu模組中，Cu電極快速擴散至Sb2Te3薄膜，並生成大量的CuTe介金屬化合物 (IMC)，導致Sb2Te3薄膜中的Te含量下降，進而生成 SbTe反位缺陷，使功率因子下降。相反地，在Ni/Sb2Te3/Ni模組中，界面處生成一連續NiTe層，成功抑制Ni電極持續擴散至Sb2Te3薄膜，但生成一較厚的IMC層將導致接觸電阻率大幅上升。在Cu/Co/Sb2Te3/Co/Cu模組中，Co成功抑制Cu擴散至Sb2Te3薄膜，同時Co也無擴散至Sb2Te3薄膜中，僅有Sb2O3生成，導致Sb2Te3薄膜中的Sb含量下降，進而生成TeSb反位缺陷，使功率因子增加。在此，提出兩個缺陷反應式來描述反位缺陷對熱電性質之影響以及薄膜的化學計量比與反位缺陷濃度之間的關係。同時，將Cu/Sb2Te3/Cu、Ni/Sb2Te3/Ni、Cu/Co/Sb2Te3/Co/Cu模組熱導率的變化進行討論。綜合熱電性質以及接觸電阻率的研究結果，Cu/Co/Sb2Te3/Co/Cu模組具有最佳的熱電表現以及熱穩定性，期以貢獻於未來Sb2Te3薄膜熱電裝置之商業化。;Issues related to carbon neutrality have received significant attention in recent years, and the world is committed to reducing carbon emissions. Therefore, research into renewable energy has gradually increased. Thermoelectric devices are a technology that can interactively convert thermal energy and electrical energy. The energy efficiency can be further improved if wasted heat is converted into usable electricity. After a thermoelectric material is modularized, the thermoelectric properties of the module are often greatly reduced because of severe interdiffusion and interfacial reactions. This study analyzed the compositional variation and measured the thermoelectric properties of Cu/Sb2Te3/Cu, Ni/Sb2Te3/Ni, and Cu/Co/Sb2Te3/Co/Cu modules that were aged to simulate real applications. The rapid diffusion of Cu in the Cu/Sb2Te3/Cu modules resulted in the massive growth of a CuTe intermetallic compound, which led to Te deficiency. Te deficiency causes the formation of antisite 〖Sb〗_Te^( ′) and reduces the power factor. In the Ni/Sb2Te3/Ni modules, the formation of a NiTe reaction layer at the interface becomes a self-barrier that inhibits Ni from diffusing to the Sb2Te3 film, but that also degrades contact resistivity. In the Cu/Co/Sb2Te3/Co/Cu modules, Co successfully inhibited Cu diffusion. Antisite 〖Te〗_Sb^. increases the power factor because the growth of Sb2O3 on the Sb2Te3 films, results in Sb deficiency. Herein, two defect reactions are proposed to explain the effects of such changes on the thermoelectric properties and the relationship between the stoichiometry of the films and the antisites concentrations. Variations in the thermal conductivity of the films are also discussed. The results show that the Cu/Co/Sb2Te3/Co/Cu modules have good thermoelectric performance and thermal stability, which should contribute to the commercialization of Sb2Te3 thin-film thermoelectric devices in the future.
