CORRECTIONS TO THE CALCULATION OF BULK ELECTRON-DENSITIES IN QUANTUM-WELLS OF HEMTS

This paper presents an improved quantum mechanical calculation of the electron density in a multi-layered high electron mobility transistor (HEMT) device structure. Extra terms arise in the integrals which desc ribe this density, and an approximation to these extra terms is derive d. This enables the integrals and their derivatives to be rapidly eval uated for the purpose of numerical simulation. The accuracy of the app roximation is demonstrated. The effect of the correction terms is illu strated in the case of a four-layer one-dimensional structure with alt ernating layers of GaAs and AlGaAs. It is shown that certain component s of the electron density are significantly increased when the extra t erms are included. It is also shown that the use of a smaller number o f eigensolutions of the Schrodinger equation produces greater accuracy when using the correction.