Hardbound. The availability of various novel materials, such as semiconductors, tailor-made polymers and ceramics, has revolutionized information processing and transmission. Since the early fifties, semiconductors have formed the backbone of different information age technologies.The fabrication of state-of-the-art semiconducting devices requires either substrates or composite structures consisting of thin epitaxial layers. Over the years, great strides have been made both in growing bulk crystals and in controlled deposition of thin homo- and hetero-epitaxial layers. Understanding of the deformation behaviour of semiconductors has facilitated the growth of high-quality crystals. Heterostructures consisting of extremely thin layers and chemically and structurally sharp interfaces can be deposited. To tailor bandgaps and electronic properties, silicon-germanium/silicon heterojunctions, mixed III-V epitaxial layers that are ordered and phase separated a