Germanium America, 30–50% of current fiber optic lines are unused dark fiber, sparking discussion of over-production and a future reduction in demand. Worldwide, demand is increasing dramatically as countries such as China are installing fiber optic telecommunication lines throughout the country. Germanium Germanium is a chemical element with symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. Pure germanium is a semiconductor with an appearance similar to elemental silicon. Like silicon, germanium naturally reacts and forms complexes with oxygen in nature. Because it seldom
Silicon-germanium Silicon-germanium SiGe ( or ), or silicon-germanium, is an alloy with any molar ratio of silicon and germanium, i.e. with a molecular formula of the form SiGe. It is commonly used as a semiconductor material in integrated circuits (ICs) for heterojunction bipolar transistors or as a strain-inducing layer for CMOS transistors. IBM introduced the technology into mainstream manufacturing in 1989. This relatively new technology offers opportunities in mixed-signal circuit and analog circuit IC design and manufacture. SiGe is also used as a thermoelectric material for high temperature applications (>700 K). The use of silicon-germanium as a semiconductor was championed by