Grain Boundary Diffusion und Grain Boundary Segregation in Cu and Cu-Based Alloys

铜导体线在非常大的系统集成应用中逐渐得到应用。晶界扩散和电迁移控制着微电子器件导体线路的使用寿命。通过允许合金化来降低这一速率是抑制电迁移失败的有效方法。寻找合适的合金元素需要了解GB的扩散和偏析行为。系统研究不同元素（Ag、Bi、Fe、Ni、Ge、Cu）在极纯Cu的多晶和双晶以及选定的Cu合金中的GB扩散是该项目的主要目标。放射性示踪法与精密连续切片技术相结合，将得到可靠的GB溶质扩散实验数据。在所谓的B-和c -动力学体系中测量的结合提供了一种新的和独特的方法来获得真正稀极限条件下溶质偏析行为的详细信息。通过Cu双晶的扩散实验，确定了能够区分线性或非线性GB偏析的偏析等温线。放射性示踪剂实验将结合使用分析和高分辨率透射电子显微镜对溶质偏析的原子细节进行研究。

Copper conductor lines are progressively used in very large system integration applications. Grain boundary (GB) diffusion and electromigration controls the service life of the conductor lines in microelectronic devices. The reduction of this rate by allowing is alloying is an effective way for inhibiting electromigration failure. The search of favorable alloying elements requires knowledge of GB diffusion and segregation behavior. Systematic investigation of GB diffusion of different elements (Ag, Bi, Fe, Ni, Ge, Cu) in poly- and bicrystals of very pure Cu and in selected Cu alloys is the main goal of the project. Application of the radiotracer method in combination with precise serial sectioning technique will result in reliable experimental data on GB solute diffusion. The combination of measurements in the so-called B- and C-kinetic regimes provides a new and unique method to obtain detailed information on the solute segregation behavior in true dilute limit conditions. By diffusion experiments with Cu bicrystals segregation isotherms will be determined that enable to distinguish between linear or non-linear GB segregation. The radiotracer experiments will be combined with a study of atomistic details of solute segregation using analytical and high-resolution transmission electron microscopy.