Nonvolatile memory based on mobile protons

We have found that mobile protons can be introduced into the gate or buried oxide layer(s) of Si-SiO₂-Si structures with high O vacancy densities via annealing treatments in a hydrogen-containing ambient (e.g. forming gas). These mobile protons are confined within the oxide layer, and their space-charge distribution is easily controlled by an applied gate bias. The resulting proton motion modulates the Si conduction layer conductivity, an effect that can be exploited to form nonvolatile memory elements; the size of the memory window is proportional to the hysteresis due to the proton motion. Speed, retention, endurance, and radiation tolerance data on test structures suggest that this effect can potentially be exploited to develop a low-power, radiation tolerant nonvolatile memory technology. The present status of the protonic memory development activity is discussed, and issues for technology insertion are highlighted