Germanium

Germanium is a chemical element; it has symbol Ge and atomic number 32. It is lustrous, hard-brittle, grayish-white and similar in appearance to silicon. It is a metalloid (sometimes considered a nonmetal) in the carbon group that is chemically similar to silicon. Like silicon, germanium naturally reacts and forms complexes with oxygen in nature.

German chemist (1838-1904)

thumb|upright=1.5|(a) Scanning tunneling microscope|STM image of germanene. (b) Profile (black line in (a)) showing step heights of ~3.2  Å. (c) High-resolution STM image (distorted by sample drift). (d) Profiles along the white continuous and dashed lines in (c) showing a ~9–10  Å separation between protrusions having heights of ~0.2  Å. (e) [[Electron diffraction pattern. (f) Model of germanene on Au(111).]] Germanene is a material made up of a single layer of germanium atoms. The material is created in a process similar to that of silicene and graphene, in which high vacuum and high tempera

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 Si1−xGex. 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).