Avalanche Breakdown Due to 3-D Effects in the Impact-Ionization MOS (I-MOS) on SOI: Reliability Issues

In this paper, we report on reliability issues concerning the impact-ionization MOS (I-MOS). For the first time, the anomalously high off current in the planar I-MOS is studied owing to light-emission experiments. We show that a first breakdown occurs at the width borders of the device, followed by the theoretical volume breakdown. This result is intensively studied through 3-D TCAD simulations. The results are correlated with electrical measurements. We finally propose and validate a degradation mechanism based on charge trapping.