a) Assume a sample is illuminated over a narrow region of its length.

a) Assume a sample is illuminated over a narrow region of its length. In a band diagram, sketch the quasi-Fermi levels in the illuminated zone and for several diffusion length on either side of the illuminated zone. Assume n-type material and space charge neutrality.b)Draw a band diagram for a forward biased p-n junction, including a sketch of quasi-Fermi levels Fn(x) and Fp(x) throughout the junction and for several diffusion lengths on either side of the junction. Explain qualitatively the variations in Fn and Fp.