Silicon, Physical and Chemical Properties

Silicon is a metalloid having the diamond structure (Fig. 1). It has the appearance of a metal (Fig. 2) but lacks all properties of metals. Modern electronics is almost exclusively (>95%) based on silicon devices and these are made from single-crystal silicon. Silica, SiO₂, is the major constituent of rock-forming minerals in magmatic and metamorphic rocks; it accounts for ca. 75% of the Earth’s crust. The basic building block of the silicates is the SiO ⁴⁻₄ tetrahedron (Fig. 3). The variety in the structures of the silicates is due to the various possible combinations of these tetrahedral, both with each other and also with other ions.

Silicon, Physical and Chemical Properties, Fig. 1

Structure of silicon