TRANSPORT PROPERTIES OF DELTA-DOPED FIELD EFFECT TRANSISTOR

Abstract

The first calculation of mobility and conductivity between source and drain as function of gate voltage in a δ-doped Field Effect Transistor is presented. The calculation was performed with a model for the δ-FET that was shown in (1). The mobility was calculated using a phenomenological expression that was presented in (2). That expression does not have empirical form, neither empirical parameter. For the first time a phenomenological expression of the conductivity is presented, which is derived from the mobility expression. The conductivity shows three different regions: a parabolic region and two linear regions. The parabolic region represents the region at which the conduction channel begins to close. On the other hand, the mobility shows a more different behavior. In the mobility there are four regions. These regions correspond to the disappearance of the different conduction channels that form the subbands of the delta- doped quantum well. The different behavior between mobility and conductivity relies on the depletion of the delta-doped quantum well as the gate potential grows.