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प्रश्न
Distinguish between intrinsic and extrinsic semiconductor. (Give any two points).
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उत्तर
| Intrinsic semiconductors | Extrinsic semiconductors | |
| 1) | Semiconductor in the pure form is known as intrinsic semiconductor. |
The semiconductor, resulting from mixing of impurity in it, is known as extrinsic semiconductor |
| 2) | Their conductivity is low | Their conductivity is high. |
| 3) | Its electrical conductivity is a function of temperature alone. |
Its electrical conductivity depends upon the temperature as well as on the quantity of impurity atoms doped in the structure |
| 4) | The number of free electrons in conduction band is equal to the number of holes in valence band. |
In these semiconductors, number of free electrons and number of holes are unequal |
| 5) | These are not practically used | These are practically used |
| 6) | In these, the Fermi energy level lies in the middle of valence band and conduction band. | In these, the Fermi energy level shifts towards valence or conduction energy band. |
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संबंधित प्रश्न
Distinguish between 'intrinsic' and 'extrinsic' semiconductors
In a p-type semiconductor, the acceptor impurity produces an energy level ______
Electronic configuration of germanium is 2, 8, 18 and 4. To make it extrinsic semiconductor small quantity of antimony is added. The correct statement is ____________.
A donor impurity results in ______.
In n-type semiconductor, the fifth electron ______.
The electron and hole concentration in a semiconductor in thermal equilibrium is given by ______.
State how a p-type semiconductor will be obtained from a pure crystal of a semiconductor.
In a pure semiconductor crystal of Si, if antimony is added then what type of extrinsic semiconductor is obtained. Draw the energy band diagram of this extrinsic semiconductor so formed.
The figure shows a piece of pure semiconductor S in series with a variable resistor R and a source of constant voltage V. Should the value of R be increased or decreased to keep the reading of the ammeter constant, when semiconductor S is heated? Justify your answer
Name the extrinsic semiconductors formed when pure germanium is doped with a trivalent impurity. Draw the energy band diagram of extrinsic semiconductors so formed.
- Statement I: By doping silicon semiconductor with pentavalent material, the electrons density increases.
- Statement II: The n-type semiconductor has net negative charge. In the light of the above statements, choose the most appropriate answer from the options given below:
In an extrinsic semiconductor, the number density of holes is 4 × 1020 m-3. If the number density of intrinsic carriers is 1.2 × 1015 m-3, the number density of electrons in it is ______.
- Assertion (A): Putting the p-type semiconductor slab directly in physical contact with the n-type semiconductor slab cannot form the pn junction.
- Reason (R): The roughness at contact will be much more than inter atomic crystal spacing and continuous flow of charge carriers is not possible.
With an increase in the temperature, the electrical conductivity of a semiconductor ______.
What type of semiconductor is obtained when a crystal of silicon is doped with a trivalent element?
The majority charge carriers in a P-type semiconductor are ______.
What is the conductivity of intrinsic semiconductors at room temperature?
What is the impurity added to a semiconductor called?
What is the semiconductor to which the dopant is added called?
To which group of the periodic table do silicon and germanium belong?
What is the valency of silicon and germanium?
From which neighbouring groups of the periodic table are dopants for silicon and germanium chosen?
Which type of dopant is arsenic (As)?
Which type of dopant is indium (In)?
What are the two types of extrinsic semiconductors?
