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A compound semiconductor is a semiconductor compound composed of chemical elements of at least two different species. These semiconductors form for example in periodic table groups 13–15 (old groups III–V), for example of elements from the Boron group (old group III, boron, aluminium, gallium, indium) and from group 15 (old group V, nitrogen, phosphorus, arsenic, antimony, bismuth).
When silicon (Si), having four valence electrons, is doped with elements from group III of the periodic table, such as boron (B) and aluminium (Al), both having three valence electrons, a p-type semiconductor is formed. These dopant elements represent trivalent impurities. Other trivalent dopants include indium (In) and gallium (Ga). [1]
The conductivity of semiconductors may easily be modified by introducing impurities into their crystal lattice. The process of adding controlled impurities to a semiconductor is known as doping . The amount of impurity, or dopant, added to an intrinsic (pure) semiconductor varies its level of conductivity. [ 26 ]
The wafers are thoroughly rinsed with deionized water between each step. [ 2 ] Ideally, the steps below are carried out by immersing the wafers in solutions prepared in fused silica or fused quartz vessels ( borosilicate glassware must not be used, as its impurities leach out and cause contamination) [ citation needed ] .
Doping of a pure silicon array. Silicon based intrinsic semiconductor becomes extrinsic when impurities such as boron and antimony are introduced.. In semiconductor production, doping is the intentional introduction of impurities into an intrinsic (undoped) semiconductor for the purpose of modulating its electrical, optical and structural properties.
A mixture of water and salt can be separated by distillation, with water as the distillate and salt as the solid residue. This is done by heating the water so it boils and leaves behind the salt. The water is cooled and the gas turns back to a pure liquid. [3] Impurities are usually physically removed from liquids and gases.
In physical chemistry and engineering, passivation is coating a material so that it becomes "passive", that is, less readily affected or corroded by the environment. . Passivation involves creation of an outer layer of shield material that is applied as a microcoating, created by chemical reaction with the base material, or allowed to build by spontaneous oxidation
In semiconductor physics, a donor is a dopant atom that, when added to a semiconductor, can form a n-type region. Phosphorus atom acting as a donor in the simplified 2D silicon lattice. For example, when silicon (Si), having four valence electrons , is to be doped as a n-type semiconductor , elements from group V like phosphorus (P) or arsenic ...