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A p-n photodiode is fabricated from a se...

A p-n photodiode is fabricated from a semiconductor with band gap of 2.8 eV. Can it detect a wavelength of 6000 nm?

Text Solution

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Energy of the photon of wavelength `lambda` is
`E =(hc)/(lambda)`
`:. " "E=(6.62xx10^(-34)xx3xx10^(8))/(6000xx10^(-9))`j=0.206 eV
The band gap of the semiconductor =2.8 eV
Since the band gap energy is more than the energy of the light photon it can not be detected.
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