Q24 of 40 Page 92

Three photo diodes D1, D2 and D3 are made of semiconductors having band gaps of 2.5eV, 2eV and 3eV, respectively. Which ones will be able to detect light of wavelength

Given wavelength is 6000x10-10m.


So, energy is eV will be,





So, the only diode with band width 2eV would be able to detect it as others won’t be able to release enough electrons.


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