{"title":"Evaluation of Cu surface diffusion on different metal liner materials for Cu reflow applications","authors":"O. van der Straten, L. W. Wangoh","doi":"10.1557/s43578-024-01427-0","DOIUrl":null,"url":null,"abstract":"<p>Cu reflow behavior was studied on various metal liners, including Co, Ru, Ta, Ti, and W. These investigations provide insight into the differences in surface diffusion characteristics of Cu along these metal liner interfaces, as revealed by structural characterization using various electron microscopy imaging techniques. In addition, the electrical properties of these metal liner/Cu stacks were investigated as a function of annealing time by evaluating changes in sheet resistance, to understand the extent to which Cu films remain continuous. Atomic force microscopy, transmission electron microscopy, and scanning electron microscopy observations provided insight into the dimensions of Cu islands formed during thermal annealing. On Ta and Ru liners, Cu surface diffusion was found to be most prominent. Compared to Ta and Ru, more Cu islands were formed per area for Co liner, exhibiting a reduced average Cu island size. Only minimal Cu island formation was observed for Ti and W liners.</p><h3 data-test=\"abstract-sub-heading\">Graphical abstract</h3>\n","PeriodicalId":16306,"journal":{"name":"Journal of Materials Research","volume":"420 1","pages":""},"PeriodicalIF":2.7000,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Materials Research","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1557/s43578-024-01427-0","RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Cu reflow behavior was studied on various metal liners, including Co, Ru, Ta, Ti, and W. These investigations provide insight into the differences in surface diffusion characteristics of Cu along these metal liner interfaces, as revealed by structural characterization using various electron microscopy imaging techniques. In addition, the electrical properties of these metal liner/Cu stacks were investigated as a function of annealing time by evaluating changes in sheet resistance, to understand the extent to which Cu films remain continuous. Atomic force microscopy, transmission electron microscopy, and scanning electron microscopy observations provided insight into the dimensions of Cu islands formed during thermal annealing. On Ta and Ru liners, Cu surface diffusion was found to be most prominent. Compared to Ta and Ru, more Cu islands were formed per area for Co liner, exhibiting a reduced average Cu island size. Only minimal Cu island formation was observed for Ti and W liners.
通过使用各种电子显微镜成像技术进行结构表征,研究了铜在各种金属衬垫(包括 Co、Ru、Ta、Ti 和 W)上的回流行为,从而深入了解了铜在这些金属衬垫界面上的表面扩散特性差异。此外,还通过评估薄层电阻的变化,研究了这些金属衬垫/铜堆的电特性与退火时间的函数关系,以了解铜膜保持连续性的程度。通过原子力显微镜、透射电子显微镜和扫描电子显微镜观察,可以了解热退火过程中形成的铜岛的尺寸。在 Ta 和 Ru 衬垫上,发现铜的表面扩散最为突出。与 Ta 和 Ru 相比,Co 衬里单位面积上形成的铜岛更多,平均铜岛尺寸更小。在 Ti 和 W 衬里上只观察到极少的铜岛形成。
期刊介绍:
Journal of Materials Research (JMR) publishes the latest advances about the creation of new materials and materials with novel functionalities, fundamental understanding of processes that control the response of materials, and development of materials with significant performance improvements relative to state of the art materials. JMR welcomes papers that highlight novel processing techniques, the application and development of new analytical tools, and interpretation of fundamental materials science to achieve enhanced materials properties and uses. Materials research papers in the following topical areas are welcome.
• Novel materials discovery
• Electronic, photonic and magnetic materials
• Energy Conversion and storage materials
• New thermal and structural materials
• Soft materials
• Biomaterials and related topics
• Nanoscale science and technology
• Advances in materials characterization methods and techniques
• Computational materials science, modeling and theory