Self-consistent Schroedinger-Poisson calculations have been employed to inv
estigate theoretically the mobility extraction for hetero-MOSFETs or HMOSFE
Ts with a thin gate oxide. In this particular case, the contribution of the
cap layer to the gate capacitance is crucial. It is shown that there is a
considerable error in the effective mobility when extracted with the common
constant capacitance approximation and that application of the split-CV me
thod is essential. (C) 2001 Elsevier Science Ltd. All rights reserved.