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Question 5.6: For the diode of Example 5–4, what is the total depletion ca...

For the diode of Example 5–4, what is the total depletion capacitance at −4 V?

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C_{j} =\sqrt{\epsilon } A\left[\frac{q}{2\left(V_{0}-V \right) } \frac{ N_{d} N_{a}}{ N_{d}+ N_{a}} \right]^{{1}/{2}}

 

=\sqrt{\left(11.8\times 10^{-14}\times 11.8\right) } \left( 10^{-4}\right) \left[\frac{1.6\times 10^{-19}}{2\left(0.695+4\right) } \left(\frac{ 10^{15}\times 10^{17}}{ 10^{15}+ 10^{17}} \right) \right]^{{1}/{2}}

 

=4.198\times 10^{-13}F

 

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