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Question
Answer in detail.
Distinguish between intrinsic semiconductors and extrinsic semiconductors.
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Solution
| Sr. No. | Intrinsic semiconductors | Extrinsic semiconductors |
| i. | A pure semiconductor is known as intrinsic semiconductors. | The semiconductor, resulting from mixing of impurity in it, is known as extrinsic semiconductors |
| ii. | Their conductivity is low at room temperature | Their conductivity is high even at room temperature. |
| iii. | 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. |
| iv. | The number density of holes (nh) is the same as the number density of free electron (ne) (nh = ne). |
The number density of free electrons and the number density of holes are unequal. |
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