Abstract
A modulation‐doped field‐effect transistor model for long‐channel devices is discussed and results presented. The model takes into account an arbitrary electrons degeneracy condition. It describes the drain current accounting for both the drift and the diffusion components in the constant mobility approximation. The additional effective electric field that arises due to dependence of the subband bottom on concentration is also taken into account. It is shown that at low temperatures (78 K) the degeneracy of the channel electrons plays an important role in the entire region of the device operation including the saturated region of the IV characteristics.