A Coupled Lattice-based Continuum Formulation for Stress and Electromigration-mediated Diffusion in Polycrystalline Solids

本研究旨在开发一种反映多晶固体中成分和力学之间耦合关系的连续体配方。电迁移效应也包括在内。其动机是模拟微结构的演变，这可能导致集成电路中金属线的失效。在热力学公式中，组成、力学和电场通过晶格级机制相互作用，由此推导出耦合场关系。然后，可以提出反映扩散蠕变、丘状形成、晶界运动、空洞形成和演化等现象复杂性的一般初始值和边值问题。该项目还将开发计算方法来解决耦合偏微分方程的结果系统。

0075989The research aims at developing a continuum formulation reflecting the coupling between composition and mechanics in polycrystalline solids. Electromigration effects are also included. The motivation is to model the evolution of microstructure, which can lead to failure of metal lines in integrated circuits. Composition, mechanics and electric fields interact via lattice-level mechanisms in a thermodynamic formulation from which the coupled field relations are derived. General initial and boundary value problems reflecting the complexity of phenomena such as diffusion creep, hillock formation, grain boundary motion, void formation and evolution can then be posed. The project will also develop computational methodologies to solve the resulting system of coupled partial differential equations.