Task8. Find the oxide charge density (Qox in Ccm-2) at the Flat-band condition (taking into account the work function difference) and at the Mid-gap condition? How many charges does this correspond to (Nox cm-2)?

 

This problem should be discussed in two situations.

First, the oxide charge density at the flat-band condition.

By using this formula:

The value of Qox is -1.045*106C/cm2

Then, we can use this formula to calculate the count of charges.

We know the value of q, this is a common value, 1.602*10-19

Then the value of NOX is 6.52*1012


Second, at mid-gap situation, we need different formulas to calculate the value of QOX, and there are the formulas:



After calculate the value of VG, deltaV is 0.422-1.35=-0.928V, and we also knew the value 

of area, so QOX is -1.14*10-6C/cm2

In the end, the value of NOX at mid-gap condition is 7.116*1012









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