The science of materials as a specific discipline is a relatively modern development. Within this rather modern field, the study of semiconductor materials is an even more recent development. Modern textbooks on materials science focus primarily on the properties of metals and second on the properties of ceramics, reflecting the commercial importance of these materials 50 years ago when the transistor was demonstrated using germanium. Today the commercial importance of semiconductor materials is comparable to that of metals and ceramics, and the advances in semiconductormaterials technology are driving rapidly growing business sectors in communications, software, and biotechnology.