Task7. Calculate the Mid-gap Voltage.

 To calculate the mid-gap voltage, we need to obtain the depletion capacitor value at mid-gap.


                                          Figure5. The a.c. equivalent circuit at mid-gap

Assuming a uniformly doped semiconductor, we can calculate the depletion capacitor value by the formula:


Then, the value of Cdep  is 3.28E-4 F/m2

Using the formula:

we can calculate the value of 1/Cmidgap.

And we know the relationship between CDep and Cdep.

With the values of CDep and COX, we can calculate the value of Cmidgap is 7.587*10-11F, and Vmidgap equals 1.35V.





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