Abstract
We have used MODFET and DHMODFET as simulation devices. The densities of the two dimensional electronic gas (2DEG) confined in the potential well can be calculated through solving the coupled Poisson and Schrodinger equations self-consistently. We studied some factors might which affect the 2DEG, including temperature, thickness of the spacer layer, doping concentration and mole fraction. We found that these factors have minor effect on the 2DEG.This is good for devices performance. Compared with other Ⅲ-Ⅴ materials, the piezoelectric effect in the Ⅲ-Nitride materials is the major factor to affect the 2DEG. The many-body effect is considered by incorporating the exchange-correlation energy to the Hartree model used for the calculations. And we found that the negative gate bias will reduce generation of the 2DEG.