Semiconductor- What is semiconductor in full notes?

The semiconductor which have resistivity between the conductor and the insulator are called semiconductors. The best semiconductor are Germanium,Silicon,Selenium etc.
In the semiconductor the number of free electron per unit volume is the order of 10^13.
Hence it resistivity lies between 10 to 100 ohm - centimetre.Apart this there is are some more difference between the conductor and semiconductor. When the temperature of the conductor is increased its resistivity increase.

But when the temperature of a semiconductor is increased its resistivity decrease. Also in the semiconductor, if impurity is mixed from outside then its electrical conductivity is very much affected which is not found in the case of conductor.

Semiconductor are of two types-

 ⦁      Intrinsic semiconductor
 ⦁      Extrinsic semiconductor 

Intrinsic semiconductor-
The semiconductor in its purest form are called Intrinsic semiconductor .

Extrinsic semiconductor -
The semiconductor which are dopped with the impurity are called extrinsic semiconductor .

1) P- type semiconductor-

The conduction property of a semiconductor can be drastically changed by diffusing a small amount of impurity in it .The process of diffusion an impurity is called doping .
If a trivalent impurity such as Aluminium is dropped in the semiconductor like Silicon then the hole produced at the position.
which are majority charge carrier in the such cases. This type of semiconductor in which holes are majority charge Carriers is called P- type semiconductor. The impurity in these are called acceptor impurity.

2) n-type semiconductor -

The semiconductor in which negative charge Carriers are larger in number than the positive charge carrier are called n -type semiconductor. In fact electrons are the majority charge carriers in case of N - type semiconductor.
It can be obtained by dropping a pentavalent impurity to the tetravalent semiconductors. such impurity which donate electrons of conduction are called Donor impurity. By doping Phosphorus in Silicon we can get n- type semiconductor.

"Keep supporting me"

Thanks guys.