Fermi shift

[ramkrishna]

Dear Sir,
In mobility calculation (http://docs.quantumwise.com/tutorials/mobility.html#id11), what is exactly meant by the Fermi shift? Is it (Ec-Ef) from the bandstructure calculation or (Ef-Ei), where Ei is the intrinsic Fermi energy (labelled zero in the band structure)?

Thanks
Ramkrishna

[Jess Wellendorff]

The Fermi shift is used to emulate a shift of the Fermi level due to doping. You sometimes need to dope the semiconductor in order to move the Fermi level closer to the conductions band in order to increase the mobility.