Ensemble Monte Carlo simulation of real space transfer (NERFET/CHINT) devices

The first self-consistent particle-field ensemble Monte Carlo model for real space transfer (NERFET/CHINT) devices will be presented. The simulations performed are in agreement with experiments and reproduce all prominent features of NERFET/CHINT structures such as, negative differential resistance, saturation of drain and substrate (injection) current at high source-to-drain voltages, and the negative transconductance (ΔI_D,sat/ΔV_sub < 0) in the saturated drain current. Negative differential resistance (NDR) can be achieved through real-space electron transfer which is based on the emission of electrons from one semiconductor layer into another semiconductor layer in the presence of high electric fields parallel to the layers (Hess, 1979). The major advantage of this mechanism over the Gunn effect is that the material parameters such as mobility ratios of adjacent layers, barrier heights, layer thicknesses can be engineered to control peak-to-valley ratios, device speeds and NDR threshold voltages. Recently a number of devices, namely negative differential resistance field effect transistor (NERFET) and charge injection transistor (CHINT), have been proposed and experimentally verified (Luryi, 1985). The purpose of this paper is to present our Monte Carlo model for the real space transfer transistors (NERFET/CHINT) and summarize our simulations which are in agreement with experiments.