Engineering variations: towards practical single-electron (few-electron) memory

The origin of device characteristic deviations of a single or a few-electrons memory, which are the most serious obstacles to achieving a practical memory, is studied from the viewpoint of fluctuation of storage dots. Our model, in which dot occupation area is essential for device characteristics, is compared to the measured characteristics of fabricated memory cells with various dot radii and densities. The potential to achieve gigabit class memory is demonstrated. Manufacturing enhancement by isolated-dots storage (MEID) is proposed as the practical benefit of nonvolatile multi-dot memories.