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Germanium is created by stellar nucleosynthesis, mostly by the s-process in asymptotic giant branch stars. The s-process is a slow neutron capture of lighter elements inside pulsating red giant stars. [57] Germanium has been detected in some of the most distant stars [58] and in the atmosphere of Jupiter. [59]
As quoted in an online version of: David R. Lide (ed), CRC Handbook of Chemistry and Physics, 84th Edition.CRC Press. Boca Raton, Florida, 2003; Section 4, Properties of the Elements and Inorganic Compounds; Physical Properties of the Rare Earth Metals
Silver, although it is the least resistive metal known, has a high density and performs similarly to copper by this measure, but is much more expensive. Calcium and the alkali metals have the best resistivity-density products, but are rarely used for conductors due to their high reactivity with water and oxygen (and lack of physical strength).
The chemical elements can be broadly divided into metals, metalloids, and nonmetals according to their shared physical and chemical properties.All elemental metals have a shiny appearance (at least when freshly polished); are good conductors of heat and electricity; form alloys with other metallic elements; and have at least one basic oxide.
It is a p-type semiconductor whose electrical properties can be tailored by doping and structural modification and has emerged as one of the simple, non-toxic and affordable material for thin films solar cells since a decade. IV-VI: 2: Tin(IV) sulfide: SnS 2: 2.2 [24] SnS 2 is widely used in gas sensing applications. IV-VI: 2: Tin telluride ...
In solid-state physics, the valence band and conduction band are the bands closest to the Fermi level, and thus determine the electrical conductivity of the solid. In nonmetals, the valence band is the highest range of electron energies in which electrons are normally present at absolute zero temperature, while the conduction band is the lowest range of vacant electronic states.
For example, nearly all metals form a significant Schottky barrier to n-type germanium and an ohmic contact to p-type germanium, since the valence band edge is strongly pinned to the metal's Fermi level. [7] The solution to this inflexibility requires additional processing steps such as adding an intermediate insulating layer to unpin the bands.
Ignoring these losses and temperature dependencies in S, κ and σ, an inexact estimate for is given by [1] [5] ¯ = ¯ [() / + /] where is the electrical resistivity, and the properties are averaged over the temperature range; the subscripts n and p denote properties related to the n- and p-type semiconducting thermoelectric materials ...