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 3D TCAD simulations. The results are correlated with electrical measurements. We finally propose and validate a degradation mechanism based on charge trapping.