What is a semiconductor? | Definition & Types
Mukesh Kumar
CBSE Teacher, Blogger, and Founder of CBSE Digital Education #cbse #education
What is a Semiconductor?
Semiconductors are those materials which have a conductivity between conductors (silver, copper, etc) and insulators (glass, diamond, etc). Classification of semiconductor:
Intrinsic Material
An intrinsic type of semiconductor material is made to be very pure chemically. As a result, intrinsic material possesses a very low conductivity level having a very few numbers of charge carriers, namely holes and electrons, which it possesses in equal amounts.
Extrinsic Material
Extrinsic types of semiconductors materials are those where a small amount of impurity is added to the basic intrinsic materials. This doping uses an element from different periodic table groups. Hence, it will either have more or fewer electrons in the valence band than the semiconductors itself. This creates either spare or shortage of electrons. In this way, two types of semiconductors are produced.
N-type Semiconductor
The N-type semiconductor material has an excess of electrons. In this way, free electrons are available within the lattices and their overall movement in one direction under the influence of a potential difference results in an electric current flow. Therefore, In N-type semiconductors the charge carriers are electron.
P-type Semiconductor
In a P-type semiconductor material, there is a shortage of electrons that is there are holes in the crystal lattice. Electrons may move from one empty position to another and in this case, it can be considered that the holes are moving. This can happen under the influence of a potential difference and the holes can be seen to flow in one direction resulting in an electric current flow. A P-type semiconductor is actually harder for holes to move than for free electrons to move and, therefore, the mobility of holes is less than that of free electrons. Holes are positively charged carries.
Semiconductor Materials
There are many different types of semiconductor materials that can be used within electronic gadgets. Each has its own advantages, disadvantages, and area where it can be used to offer the optimum performance.