Question
What is called extrinsic semiconductor? Explain doping process.
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Answer
Extrinsic semiconductor : The conductivity of intrinsic semiconductors is very low at room temperature. Therefore, to increase the conductivity, a small amount of certain element of the third or fifth group is added to the semiconductor. The semiconductor obtained in this way is called impurity semiconductor or extrinsic semiconductor.
Doping : The process of introducing impurity atoms into a intrinsic semiconductor is called doping.
To obtain extrinsic semiconductor, approximately from $(10)^6$ to $(10)^{10}$ atoms are one atom is of impurity element in intrinsic semiconductor.
Doping : The process of introducing impurity atoms into a intrinsic semiconductor is called doping.
To obtain extrinsic semiconductor, approximately from $(10)^6$ to $(10)^{10}$ atoms are one atom is of impurity element in intrinsic semiconductor.
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