Extrinsic Semiconductor

Semiconductors are materials that have conductivity that is midway between that of conductors, which are usually metals, and nonconductors, which are usually ceramics. Semiconductors can be pure elements like germanium or silicon, or compounds like gallium phosphide. Physics explains the concepts, features, and mathematical approaches used to regulate semiconductors.

Extrinsic Semiconductor

Extrinsic semiconductors have had a regulated rate of contamination added to them in order to make them conductive.

Integral semiconductors can be doped to generate extrinsic semiconductors, just as insulating materials can be doped to form semiconductors.

Extrinsic semiconductors are divided into two types as a result of doping: atoms with an extra electron (n-type for negative, from group V) and subatomic particles with only one or a few electrons (p-type for positive, from group III).

Doping is the process of inserting impurities into a semiconductor that is completely genuine, or intrinsic, in order to change its electrical properties. The kind of semiconductor determines the impurities. Extrinsic semiconductors are used by people who have a low to moderate level of doping.

N-type semiconductor:

An n-type semiconductor is formed when a tetravalent

element such as Silicon or Germanium is doped with a pentavalent element such

as Arsenic (As) or Antimony (Sb). As a result, one atom of the pentavalent

element replaces one of the four valent elements in the crystal lattice.

After the doping procedure, all five pentavalent atom electrons form strong bonds with their tetravalent neighbors, and the fifth electron forms a weak bond with its parent element. To ionize the fifth electron, only a small amount of energy is required. Even at ambient temperature, the fifth electron is free to roam around despite being in the crystal structure of the tetravalent element.

P-type semiconductor:

A P-type semiconductor is created when a tetravalent element like silicon or germanium is doped with a three-valent element like aluminum (Al), indium (In), and so on. Three of the tetravalent element’s four electrons form a covalent bond with the trivalent element’s three electrons after doping. The fourth electron has no electron with which to attach since there is a one-electron deficit.

As a result, a void or hole forms, and it is necessary to fill it. As a result, an electron in a nearby atom’s outer orbit gets a chance to leap into the void and fill it. One electron is taken from the system in this fashion, leaving a void or a hole in its place. The hole can then be used for conduction.

Doping

Doping is the process of introducing contamination into a semiconductor. The amount and kind of impurity introduced into the material during extrinsic semiconductor production must be closely monitored. In most cases, one impurity atom is added for every 108 semiconductor atomic nuclei.

To make a semiconductor crystal more adaptive, impurity is added to it to enhance the amount of free electrons or holes. A significant number of free electrons will exist if a pentavalent contaminant with five valence electrons is injected into a clean semiconductor. A significant number of holes will occur if a quadrivalent impurity with three valence electrons is injected into the semiconductor. N-type semiconductors and P-type semiconductors are the two sorts of extrinsic semiconductors based on the type of uncleanliness used.

Conclusion

We have studied everything we know about p-type semiconductor, extrinsic semiconductor, semiconductor types and all topics related to All About Extrinsic Semiconductor.

A semiconductor is a substance with electrical properties that fall between those of an insulator and those of a conductor. Si and Ge are the most well-known semiconductors. Semiconductor types are of two types: extrinsic (p-type and n-type). The intrinsic type of semiconductor is pure, but the extended type contains impurities to make it conduct. At ambient temperature, intrinsic conductivity will be nil, whereas extrinsic conductivity will be modest.