N-type (for example add Antimony)
The are materials which have Pentavalent impurity atoms (Donors) added and conduct by the "electron" movement and are called as N-type Semiconductors. In these types of materials:
- Donors are positively charged.
- There exists large number of free electrons.
- A small number of holes in the relation to number of free electrons.
- Doping gives:
- the positively charged donors.
- the negatively charged free electrons.
- Supply of energy gives:
- the negatively charged free electrons.
- the positively charged holes.
P-type (for example add Boron)
These are materials which have Trivalent impurity atoms (Acceptors) added and conduct by the "hole" movement and are known as, P-type Semiconductors.
In these types of materials are:
- Acceptors are charged negative.
- Large number of holes is there.
- There is small number of free electrons in relation to number of holes.
- Doping provides:
- acceptors which are negatively charged.
- holes which are positively charged.
- The supply of energy gives:
- positively charged holes.
- negatively charged free electrons.
and P and N-types both as a whole, are electrically neutral.