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In a photodiode,the conductivity increas...

In a photodiode,the conductivity increases when the material is exposed to light.It is found that the conductivity changes only if the wavelength is less than 620nm.What is the band gap?

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Band gap = energy need to over come the gap
` (hc)/(lambda) = (1242eV-nm)/(620nm)`
` = 2.0eV`
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HC VERMA-SEMICONDUCTOR AND SEMICONDUCTOR DEVICES-Exercises
  1. Suppose the energy liberated in the in the recombination of a hole-ele...

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  2. find the maximum wavelength of electromagnetic radiation which can cre...

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  3. In a photodiode,the conductivity increases when the material is expose...

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  4. Let (Delta)Edenote the energy gap between the valence band and the con...

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  5. The conductivity of a pure semiconductor is roughly proportional to T^...

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  6. Estimate the porportion of boron impurity which will increase the con...

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  7. The product of the hole concentration and the conduction electron conc...

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  8. The conductivity of an intrinsic semiconductor depends of tempareture ...

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  9. A semiconducting material has a band gap if 1 eV.Acceptor impurities a...

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  10. In a p-n junction, the depletion region is 400nm wide and and electric...

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  11. The potential barrier exists across the junction is 0.2volt.What minim...

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  12. In a p-n junction,a potential barrier of 250 mev exsists across the ju...

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  13. When a p-n junction is reverse-biased,the current becomes almost const...

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  14. The drift current in a p-n junction is 2.0(mu)A. Estimate the number o...

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  15. The current-voltage characteristic of an ideal p-n junction diode is g...

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  16. Consider a p-n junction diode having the characterstic i=i0(e^eV//kT-1...

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  17. Calculate the current through the circuit and the petential difference...

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  18. Each of the resistance shown in figure has a value of 20 Omega.Find th...

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  19. Find the current through the resistance in the circuits shown in figur...

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  20. What are the readings of the ammeterA1and A2shown in figure.Neglect th...

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