Abstract
A new model for the capacitance-voltage relation of a HEMT is presented. The model uses three physically motivated capacitive terms in series. TheC(V)expressions are derived using the quantum mechanical triangular potential well model and the two-dimensional electron-gas charge-control model. These expressions provide further physical insight into the AlGaAs heterosystem. The results obtained should be readily applicable to such techniques as DLTS and otherC(V)interface measurement methods. The equations derived will also serve as a basis for analytical and circuit modeling of HEMT structures.