Question
Question: A p – n photodiode is made of a material with band gap of 2 eV. The minimum frequency of the radiati...
A p – n photodiode is made of a material with band gap of 2 eV. The minimum frequency of the radiation that can be absorbed by the material is nearly
(Take hc = 1240 eV nm)
A
1×1014Hz
B
20×1014Hz
C
10×1014Hz
D
5×1014Hz
Answer
5×1014Hz
Explanation
Solution
: Here, Eg=2eV
Wavelength of radiation corresponding to this energy is
λ=Eghc=2eV1240eVnm=620nm
Frequencyυ=λc=620×10−9m3×108ms−1=5×1014Hz