Chapter 1, Problem 1.23P

The zero−biased junction capacitance of a silicon pn junction is $C_{jo}=0.4\text{pF}$ . The doping concentrations are $N_a=1.5\times {10}^{16}{\text{cm}}^{-3}$ and $N_d=4\times {10}^{15}{\text{cm}}^{-3}$ . Determine the junction capacitance at (a) $V_R=1\text{V}$ , (b) $V_R=3\text{V}$ , and (c) $V_R=5\text{V}$ .