Modeling the Effects of Heavy Charged Particles on MOSFETs (Metal-Oxide-Semiconductor Field Effect Transistors)

摘要

A simple model to characterize the effects of heavy charged particles on metal-oxide semiconductor field-effect transistors (MOSFET) is presented. The model is applied to experimental results provided by the Air Force Weapons Laboratory, and an attempt made to simulate saturation phenomena observed in the threshold voltage change. The model assumes all trapped holes are within a few nanometers of the oxide-semiconductor interface, and takes into account the resultant counter electric field, and its effect on the fraction escaping recombination. An equation relating threshold voltage change as a function of dose is derived and used, but does not duplicate the saturation effect. This is because the charge trapped near the interface reduces the internal oxide electric field very little. However, similarities in p-channel and n-channel MOSFET damage sensitivities indicate considerable bulk charge trapping. This would modulate the internal electric field considerably. To determine whether this accounts for saturation will necessitate refinement of the model, taking hole transport and bulk trapping into account.