Crystalline and Porous Silicon

Crystalline Si (c-Si) has many advantages over other semiconductor materials: low cost, nontoxicity, practically unlimited availability, and decades of experience in purification, growth and electronic device fabrication. Nanostructured Si possesses numerous unique merits, including outstanding electronic and optical properties, substantial surface-to-volume ratios, and easy surface modification. The first identified self-organized nanostructured Si was porous Si (PSi), which can be considered Si with a network of voids. Historically, PSi is thought to be a kind of “precursor” to black Si. Section 1.1 presents the basic concepts and properties of c-Si necessary to explain some of the features of nanostructured Si. The next sections focus on the main properties and practical aspects of the formation and applications of PSi. Comprehensive information about PSi can be found in monographs, book chapters, and review manuscripts.