Germanium

Name:
Germanium
Detailed information:

M Formula:	Ge
Properties:
Grayish-white solid. A p-type semiconductor, conductivity depends largely on added impurities, d 5.323, mp 937.4C, bp 2830C, oxidizes readily at 600–700C, does notvolatilize to approximately 1350C, Mohs hardness 6. Attacked by nitric acid and aqua regia; stable to water, acids, and alkalies in the absence of dissolved oxygen.
Derivation:
Recovered from residues from refining of zinc and other sources, by heating in the presence of air and chlorine. It is also present in some coals and can be recovered from theirash.
Occurrence:
Missouri, Kansas, Oklahoma.
Method of Purification:
The chloride is distilled and then hydrolyzed to the oxide, which is reduced by hydrogen to the metal. Zone melting is used for final purification. Single crystals are made by vaporization of germanium diiodide. The impurities in germanium are of controlling importance in its use in transistors. These are added to high-purity germanium in trace amounts during growth of single crystals.
Grade:
Transistor, i.e., impurities 1 part in 1010.
Available Forms:
Ingots, single crystals, pure or doped, powder.
Use:
Solid-state electronic devices (transistors, diodes), semiconducting applications, brazing alloys, phosphors, gold and beryllium alloys, infrared-transmitting glass.