Linear regression

A pn junction has the doping profile sketched below. Throughout the problem assume the
carrier concentrations may be neglected (n=0, p=0) in the 0 ≤ x ≤ xi region of the diode.
a. What is the built-in voltage across the junction? Justify your answer
b. Invoking the depletion approximation, make a sketch of the charge density inside
the diode versus x.
c. Obtain an analytical solution for the electric field, E(x) at all points inside the
depletion regions (-xp ≤ x ≤ xn). Show all steps and also make a sketch of E(x).
Midterm 2, ECE 448- Spring 2022, UIC Name:
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d. Draw the energy band diagram for the diode under equilibrium conditions. Clearly
indicate x = 0 and x= xi points on your diagram.