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प्रश्न
Name the two types of atoms used for doping of Ge/Si.
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उत्तर
Doping increases the conductivity of a semiconductor.
For doping pure Si, Ge, and pentavalent phosphorus is used to convert it to the n-type semiconductor.
Trivalent aluminium is used to convert pure Si, and Ge to the p-type semiconductor.
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संबंधित प्रश्न
In an intrinsic semiconductor the energy gap Egis 1.2 eV. Its hole mobility is much smaller than electron mobility and independent of temperature. What is the ratio between conductivity at 600K and that at 300K? Assume that the temperature dependence of intrinsic carrier concentration niis given by
`"n"_"i" = "n"_0 exp(- "E"_"g"/(2"k"_"BT"))`
where n0 is a constant.
Answer in detail.
Distinguish between intrinsic semiconductors and extrinsic semiconductors.
Let nh and ne be the number of holes and conduction electrons respectively in a semiconductor. Then ______.
In a semiconductor, the number of holes and number of free electrons are represented as 'nh' and 'ne' respectively. Which one of the following statements is TRUE for the semiconductor?
In a pure or intrinsic semiconductor, valence band holes and conduction-band electrons are always ______.
Hole is ______.
Two crystals C1 and C2, made of pure silicon, are doped with arsenic and aluminium respectively.
Why is doping of intrinsic semiconductors necessary?
A pure semiconductor has equal electron and hole concentration of 1016 m-3. Doping by indium increases nh to 5 × 1022 m-3. Then, the value of ne in the doped semiconductor is ______.
Answer the following giving reasons:
Impurities are added to intrinsic semiconductors.
- Assertion (A): The resistance of an intrinsic semiconductor decreases with an increase in its temperature.
- Reason (R): The number of conduction electrons as well as hole increase in an intrinsic semiconductor with the rise in its temperature.
