Drawing No. EH–MT–013 // Engineering Materials
Germanium Properties
Reviewed August 2026
Germanium is a dense, brittle elemental semiconductor with lower thermal conductivity and lower melting temperature than silicon.
Representative properties
The stated basis, temperature and direction are part of the value. Switch units without changing the physical reference.
What changes these properties?
Engineering variability
- Doping and temperature affect thermal/electronic properties.
- Fracture strength is not a stable bulk constant for polished wafers or optical components.
- Thermal conductivity falls strongly with temperature and defect concentration.
- The [100] elastic values should not be used blindly for other crystal orientations.
Selection note
Used in infrared optics, radiation detectors, semiconductor devices and specialized substrates where its electronic/optical properties justify cost and brittleness.
Where a property is shown as qualitative rather than numeric, that is intentional: the selected source or the material physics does not justify a single comparable scalar.
How to interpret this material
Stiffness
Young’s modulus describes elastic stiffness. For crystals and composites, orientation can make one scalar modulus only a directional reference.
Strength / failure
Ductile metals can use yield and tensile strength. Brittle ceramics/semiconductors and anisotropic composites require fracture, flexural or directional strength descriptions instead.
Thermal response
Conductivity, heat capacity and expansion are temperature dependent. The last column is a melting or transition descriptor only where that physical concept is appropriate.
Technical sources
The database favors manufacturer, industry, government or academic technical references and labels secondary condition-specific datasets when a primary source does not expose a complete property set.