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.