What are semiconductors? Give example.

1 Answer

Answer :

Substances that have conductivity between that of conductors and insulators are called semiconductors. Example: Silicon, Germanium

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Description : How are extrinsic semiconductors classified?

Last Answer : Extrinsic semiconductors are classified into two types depending upon the type of impurity added into a) n-type semiconductor b) p-type semiconductors.

Description : What is the reason for the conductivity of semiconductors?

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Last Answer : Substances that do not allow electric current to pass through them are called insulators. Example: Plastic, rubber, wood, glass etc.

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Last Answer : Substances that allow electric current to pass through them are called conductors. Example: Metals like copper, aluminium etc.

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Last Answer : The temperature below which material becomes superconductor is called critical temperature.

Description : What is meant by superconductivity?

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Last Answer : Oscillator is a device to produce electric oscillations of a desired frequency.

Description : Mention the applications of transistor.

Last Answer : a) Transistor is used in amplifier. b) It is used in oscillator. c) It is used in switching circuits.

Description : Write the principle of a transistor or amplifier.

Last Answer : A small change in the input signal (voltage) results a large change in the output signal (voltage).

Description : Write about the biasing of a transistor.

Last Answer : Emitter base junction is forward biased while collector base junction is reverse biased.

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Description : What is a transistor? Name its three regions.

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Description : Mention the different types of diodes and one use of each.

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Description : Mention the applications of a diode.

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Description : Mention the characteristics of a diode.

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Description : What is a rectifier?

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Last Answer : In reverse bias there is a small flow of current due to minority charge carries electrons in p region and holes in n region.

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Last Answer : The external voltage applied to make p-n junction biased is called bias voltage.

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Last Answer : When an external source of e.m.f is connected to a p-n junction, it is said to be biased.

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Last Answer : The thin region around the junction containing immobile positive and negative charges is called depletion region.

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Last Answer : The potential difference that is established due to the diffusion of electrons and holes across the boundary in the p-n junction is called junction voltage. The junction potential is 0.7v for Silicon and 0.3v for Germanium.

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Last Answer : The junction that is obtained when a p-type semiconductor and an n-type semiconductor are kept in contact is called p-n junction.

Description : What is a semiconductor diode or junction diode?

Last Answer : A diode is a single crystal of semiconducting material which is doped one side with a donor impurity and the other side with acceptor impurity.

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Last Answer : A semiconductor in which the number of holes and electrons are equal is called intrinsic orpure semiconductor.

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