Characteristics of planar doped FET structures

The recent demonstration of single atomic planes of doping using molecular beam epitaxy gives rise to the possibility of single plane FET´s with the channel confined to the dopant plane. In this paper an analysis of the Structure is presented which takes account of the spread of the free-carrier density normal to the plane. This rigorous analysis is compared with the simple case of a plane of free carriers. Under certain conditions the simple model gives good agreement with the exact analysis but for shallow, low-density planes, substantial departures from the simple model occur.