Conductivity of a photodiode starts changing only if the wavelength of incident light is less than $660 nm .$ The band gap of photodiode is found to be $(\frac{X}{8}) eV .$ The value of $X$ is:
(Given $h = 6.6 \times 10^{- 34} J s, e = 1.6 \times 10^{- 19} C$ )

Question

Conductivity of a photodiode starts changing only if the wavelength of incident light is less than $660 nm .$ The band gap of photodiode is found to be $(\frac{X}{8}) eV .$ The value of $X$ is:

(Given $h = 6.6 \times 10^{- 34} J s, e = 1.6 \times 10^{- 19} C$ )

Aicharya · Accepted Answer

Given: Threshold wavelength = 660 nm . Therefore, energy required(or band gap energy) E g = h c λ = 6 . 6 × 10 - 34 × 3 × 10 8 660 × 10 - 9 J = 6 . 6 × 10 - 34 × 3 × 10 8 660 × 10 - 9 × 1 . 6 × 10 - 19 eV = 15 8 eV So, X = 15 .

Conductivity of a photodiode starts changing only if the wavelength of incident light is less than 660 nm .…

Solution