Publisher's Synopsis
Grain boundaries are interfaces where crystals of different orientations meet. A grain boundary is a single-phase interface, with crystals on each side of the boundary being identical except in orientation. The term "crystallite boundary" is sometimes, though rarely, used. Grain boundary areas contain those atoms that have been perturbed from their original lattice sites, dislocations, and impurities that have migrated to the lower energy grain boundary. For polycrystalline films, grain boundaries, surface, interface, and internal stress can be sources of internal energy. Minimization of all the energies can, in principle, determine the competition between the variously oriented and stressed growing grains, which in turn gives rise to the abnormal grain growth texture. Grain boundary migration plays an important role in many of the mechanisms of creep. Grain boundary migration occurs when a shear stress acts on the grain boundary plane and causes the grains to slide. This means that fine-grained materials actually have a poor resistance to creep relative to coarser grains, especially at high temperatures, because smaller grains contain more atoms in grain boundary sites. Grain boundaries also cause deformation in that they are sources and sinks of point defects. Voids in a material tend to gather in a grain boundary, and if this happens to a critical extent, the material could fracture. Grain Growth in Polycrystalline Materials presents investigations on grain growth phenomena and their observation in various materials: metals and alloys, ceramics, sintered materials, thin films, etc. It focuses on the evolution of grain growth textures in drawn silver and copper wires, nanocrystalline deposits such as Fe-Ni alloy electrodeposits, Ni electrodeposits, electroless Ni-P deposits, electroless Ni-Co-P deposits, electroless Ni-Cu-P deposits, and copper interconnects will be discussed. In semiconductor films, as in other materials, grain growth stagnation coupled with texture-selective driving forces leads to secondary grain growth, the rate of which is higher in thinner films. Self ion-bombardment enhances the rate of pre-stagnation grain growth, and doping of Si with electron donor leads to enhanced pre-stagnation grain growth as well as surface-energy-driven secondary grain growth. The effects of ion-bombardment and dopants on grain growth in Si can be understood in terms of associated increases in point defect concentrations and the effects of point defects on grain boundary mobilities.
