n-type semiconductor

Silicon doped with donors, where electrons are the majority carriers.

What you’ll learn

How donor doping works
Majority vs minority carriers
Where n-type regions are used

Why it matters

n-type and p-type regions are the two ingredients of every junction and transistor.

Explanation

Adding a group-V donor such as phosphorus or arsenic gives each dopant atom a spare electron that is easily freed. Electrons become the majority carriers and holes the minority, so current is carried mainly by negative charge — hence 'n-type'.

The electron concentration is set by the donor dose, making conductivity predictable and tunable.

Visual explanation

A lattice dominated by free electrons (–), with a few holes as minority carriers.

Key terminology

Majority carrier: The more abundant carrier (electrons in n-type).
Minority carrier: The scarcer carrier (holes in n-type).

Example

An n-type source/drain region feeds electrons into an NMOS transistor's channel.

Common mistakes

Watch out for:

Thinking n-type material is negatively charged overall — it stays electrically neutral.

Real-world application

The source and drain of NMOS transistors are heavily n-type.

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