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n-type semiconductor, Meaning (SPM Physics)

A semiconductor doped so that free electrons are the majority charge carriers.

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Englishn-type semiconductor
Bahasa MelayuSemikonduktor jenis-n
中文N型半导体

Definition

A semiconductor doped so that free electrons are the majority charge carriers.

Electronics

In exam terms

An n-type semiconductor is a semiconductor that has been doped so that free electrons are the majority charge carriers. It is made by adding a pentavalent impurity (an atom with five valence electrons, such as phosphorus) to pure silicon; four electrons bond with silicon and the fifth is free to move and carry current.

Example of correct use: in an n-type semiconductor the current is carried mainly by the extra free electrons, while positive holes act only as the minority carriers.

Do not confuse it with…

Do not confuse an n-type with a p-type semiconductor. In n-type the majority carriers are negative electrons (added by a pentavalent impurity); in p-type the majority carriers are positive holes (added by a trivalent impurity).

Both are still electrically neutral overall.

In Paper 2 you may be asked to explain how an n-type is formed or to state its majority carrier; name a pentavalent dopant and say the extra electron is free to conduct.

Source: DSKP KSSM Physics Form 4 and 5 (Versi English) (Bahagian Pembangunan Kurikulum (BPK), KPM)

Frequently asked questions

What are the majority charge carriers in an n-type semiconductor?
Free electrons are the majority carriers; positive holes are the minority carriers.
How is an n-type semiconductor made?
By doping pure silicon with a pentavalent impurity such as phosphorus, which provides an extra free electron per atom.
Is an n-type semiconductor negatively charged overall?
No. Although its majority carriers are electrons, the material as a whole is electrically neutral.

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