Question

What is the resistance of an intrinsic semiconductor at 0K?

Answer 1

Hint: Semiconductors are defined as the materials whose conductivity is between conductors and non-conductors or insulators. They have conductivity lower than conductors and higher than insulators. The examples of semiconductors are gallium arsenide or pure elements, such as germanium or silicon.

Complete answer:
In order to answer this question, we need to understand the two terms, which are resistance and intrinsic semiconductor.
The property of a conductor due to which it opposes the flow of the electric current in a particular direction through it is known as resistance. Materials which offer low resistance are known as conductors whereas the materials which offer high resistance are known as insulators.
Intrinsic semiconductors are one of the types of semiconductor. It is a pure form of semiconductor crystal because no impurity has been added in it. Since it is the pure form, hence it contains only tetravalent elements. In an intrinsic semiconductor, the number of holes which are present in the valence band is exactly equal to the number of electrons which are present in the conduction band.
The carriers are completely absent in the conduction band of an intrinsic semiconductor at temperature 0 K. Therefore, we can say that the conductivity is zero and hence resistivity is infinity. Thus, it can be said that the resistance is infinite of an intrinsic semiconductor at temperature 0 K.

Note:
The main difference between intrinsic semiconductor and extrinsic semiconductor is impurity. Concentration of doping must be kept in mind because concentration of doping is the factor that is responsible for changing concentration of free charges which makes the current flow. It is important to note that a small amount of impurity must be added. It often happens that when a large amount of impurity is added, then the structure of the crystal gets changed.