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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?

A

1.0 eV

B

3.2 eV

C

6eV

D

2.0 eV

Text Solution

Verified by Experts

The correct Answer is:
D
The band gap `E_g`
`(hc)/lambda =((6.63 xx 10^(-34))xx(3xx 10^8))/(620xx10^(-19)) = 3.2 xx 10^(-19 )J = 2.0 eV`.
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