Onset of Inversion for FD Statistics:



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Onset of Inversion for FD Statistics:

Let us define the entering in inversion at the oxide/semiconductor interface in the standard way by , for -type of semiconductor. Replacing in A.5, taking advantage of A.4 and

 

we derive

 

The potential may be written as

 

where is the potential at the onset of inversion for the ideal band and MB statistics. Band-gap narrowing and degeneration tend to cancel each other in expression A.23. Like most quantities in our analysis, is also only slightly influenced by the degeneration due to FD statistics. For example, assuming , the sum contributes to with only at and with at , both being less than the small contribution of the electrical band-gap narrowing at this doping level. In the preceding calculation we have accurately accounted for the temperature dependence of and .



Martin Stiftinger
Sat Oct 15 22:05:10 MET 1994