Drain leakage mechanisms in fully depleted SOI devices with undoped channel

摘要

The leakage mechanisms in fully depleted (FD) SOI transistors with undoped channel are investigated. These devices -contrary to partially depleted devices-show a strong V_(DS) dependence of the leakage currents. Energy balance simulations including band to band tunneling effects and impact ionization have been carried out. Contrary to drift diffusion calculations these simulations can account for the experimental data and show that the two effects can be separated. In order to reduce these leakage effects the design of the drain has to be optimised.