Semiconductor Material

Semiconductor material---in physics that studies of solid, we know there arematerials that are conductors, Insulators, and Semikondutor. Before continuingyour reading activities, help us to click the image on the side. In this article wewill focus on discussion of a semiconductor material. Semiconductor material isa material that can be turned into a good conductor, when given enough energy to make it a conductor.

Certain materials such as carbon, Silicon, germanium, and sebagainnya is not asconductors such as copper or not as an insulator like glass. In other words, the resistivity of the material located between a conductor and an insulator. Suchmaterials are classified as semiconductors. Semiconductors have properties that are useful and very intensively used in electronic circuits. For example, a transistor is a semiconductor device, quickly and almost total replaces thevacuum tube on each application. The transistor is just one of thesemiconductor device family, many other semiconductor devices which are becoming increasingly very popular, for example IC.

Semiconductor materials

It is not easy for defining semiconductors if it were to cover all the physicalproperties. But in General, its electrical conductivity is defined based onsemiconductors, namely Semiconductor is a material that has a resistivity (10 ^-4)
up to 0.5 Ohmmeter) between a conductor and an insulator, e.g.
carbon, Silicon, germanium, selenium, etc. Note the following table!

Compare the resistivity of the material above it appears that the resistivity ofgermanium (semiconductor) is quite high compared to copper (conductors) butis quite low in comparison to glass (insulator). This memumjukkan that theresistivity of a semiconductor material is between a conductor and an insulator.But it would be wrong if it is said that semiconductor material as resistant. For example the nichrome is one the highest resistant materials, have a much lowerresistivity than germanium. This shows that electrically germanium cannot be considered a conductor or an insulator or a resistant material. It is possible tomake a mixture of metals (alloy) that resistivitasnya is located in the range ofsemiconductors but the blend cannot be considered as a semiconductor. In fact,a semiconductor has a number of special properties that distinguish it from theconductor, insulating and resistant materials.
The Properties Of Semiconductor Materials
  1. The resistivity of a semiconductor on insulator of smaller but larger than theconductor.
  2. Semokonduktor has a negative temperature coefficient of resistance, namely that the resistance of a semiconductor decreases with temperature increase and vice versa. For example, germanium into insulators at low temperature but it is a good conductor at high temperature.
  3. When the right metallic ketakmurnian (such as arsenic, gallium, etc.) added to the semiconductor material, then the conduction properties of arusnya changed.This is the nature of the most typical and important.
Atoms of each element are bound together by the binding action of valence electrons. Bonds is related to the fact that the existence of the tendency of eachatom to complete its final orbit with need 8 electrons. But a lot of material that was his final orbit not complete its final orbits that do not have 8 electrons. This makes active atoms enter into agreement with other atoms to fullfill the orbitalelectrons in his last 8. To that end, the atoms can be lost, ketambahan or usingshared electron valensinya
with other atoms. In a semiconductor material, a bond is formed with the use ofshared valence electrons. The bonds were known as Covalent bonds. In theformation of Covalent bonds, each atom contributed the same number ofvalence electrons and electron donation that is shared by the atoms whichinvites the formation of Covalent bonds in it. The following image showsCovalent bonds between atoms germanium. An atom of germanium has 4valence electrons. These tend to each atom of germanium has 8 electrons in its final orbit.


The position of each atom of germanium itself is located between four othergermanium atom. Every neighboring atoms using together one valence electrons towards its central atom. In this cooperation, the central atomcompletes its final orbit with 8 electrons circle around the point. In this way, the central atom building Covalent bonds. The following principal matters relating to covalent bond:
  1. Covalent bonds are built with shared use of valence electrons.
  2. In the formation of Covalent bonds, each of the valence electrons of an atomform bonds directly with the valence electrons of an atom. In other words, the valence electrons are associated with certain atoms. For this reason, the valenceelectrons in a semiconductor material is not free. 
A material in which the atoms or molecules arranged in a regular pattern known as Crystal. All semiconductor material structure as crystals. Therefore a piece ofgermanium in germanium crystals commonly referred to.

Postingan terkait:

Belum ada tanggapan untuk "Semiconductor Material"

Post a Comment