Interfacial energy: bicrystals of semi-infinite crystals

Crystalline materials are normally bounded by surfaces and interconnected by interfaces defects. These defects greatly influence the properties of structural materials. Their influence is normally quantified in terms of defect energies - the surface and interfacial free energies - that play, e.g., a decisive role in shaping the thickness uniformity of epilayers, a feature of great importance in the fabrication of devices. The quantification of these defect energies and their dependence on the interfacial misfit between the crystals are thus highly desirable objectives. Embedded atom method (EAM) interaction potentials are used for purposes of quantification. Their advantages and disadvantages are noted. The interpretation of the results is greatly facilitated by application of optimum Fourier coefficients. Predictions of significance, that can be inferred from sample calculations, are: (i) that the interfacial energy is normally not small compared to the surface energies and (ii) that the variation of interfacial energy with misfit is significant and can be understood in terms of the optimum Fourier coefficients. (C) 2001 Elsevier Science Ltd. All rights reserved.