I have an error that the PF mobility is reduced by 11 orders of magnitude.
The PF equation is attached. I can see that the effective barrier is reduced by the electric field. But let's plug in all the values.
Where u0 is the low-field mobility
Assuming the electric field is negligibly small for the time being,
a trap energy level (or activation energy) of 0.65 eV,
room temperature 300K,
electric charge q and Boltzmann constant kB at normal values.
The exponential term gives a value of 1.2x10-11 which must be wrong. My understanding is that, at low electric field, the exponential term should go to unity. At higher field, the mobility is enhanced by PF process. Am I making any mistakes with the assumptions? Thanks.
Dear Hongtu,
welcome!,
The expression you brought for the mobility tells us that it will be affected by a thermionic emission process over a barrier phiB. I t will be affected also by an accelerating electric field E, where it will reduce the barrier phiB. So, under your assumptions, your calculation is okay since the barrier is high,temperature is normal and there is no assistance from the electric field as you assumed it zero. The exponential term can approach only one, if the exponent of the e term gets zero. This may occur at very high electric fields with this value of phiB.
Best wishes
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