How many valence electrons are there in doped materials of p-type and n-type materials?

Answer 1

1. N and P-type Semiconductors

Neither pure silicon(Si) nor germanium(Ge) are great conductors. They form a crystal

lattice by having each atom share all of its 4 valence electrons with neighbouring atoms.

The total of eight electrons can not easily be jiggled out of place by an incoming current.

If , however, the crystalline array is "doped"(mixed with an impurity) with arsenic which

has five valence electrons, the behaviour of the lattice will change. Four bonds will be

still be made but there will be a leftover electron that can wander through the crystal.

This is called an n-type semiconductor.

Boron can also be used to dope a pure crystal of silicon. But since boron only offers 3 of

the four electrons that a silicon atom needs, each silicon center is left with a hole.

Semiconductors made in this manner are called p-type.

In a p-type material if an atom from a neighbouring atom fills the hole, it will leave a

hole adjacent to it. This process will continue in a domino effect and the hole will be

moving in the direction opposite to electron-flow. In reality the atoms are remaining fixed

in the lattice, but there is an illusion that the holes are physically moving.

Answer 2

N-type or P-type does not mean that the semiconductor has a net charge. It refers to the majority carrier in the semiconductor. N-type semiconductors have an abundance of free electrons (negative carrier) and P-type semiconductors have an abundance of holes (positive carriers).

Answer 3

3 electon in valence band in p-typye material and 5 electron in N-type material