When a pentavalent impurity is added to a pure semiconductor it becomes______
When a pentavalent impurity is added to a pure semiconductor it becomes______
Right Answer is:
n-type
SOLUTION
N-type semiconductors are created by doping an intrinsic semiconductor with donor impurities (pentavalent impurity).
- In an n-type semiconductor, the Fermi energy level is greater than that of the intrinsic semiconductor and lies closer to the conduction band than the valence band.
- The “n” stands for negative because their conduction is due to a transfer of excess electrons.
- A pentavalent atom, the one that has five valence electrons is called a donor.
- Each donor produces one free electron in a silicon crystal.
- In an n-type semiconductor, the free electrons are the majority carriers, while the holes are the minority carriers because the free electrons outnumber the holes.