Simulation of a quantum-dot flash memory

We present the simulation of a flash memory in which the floating gate is replaced by a silicon quantum dot. Unlike conventional flash memories, this device promises the advantage of self-limited direct charging of the floating gate with a low writing voltage,thus allowing one to overcome hot carrier degradation problems. Due to the small dimensions of this memory device, quantum effects are expected to play an important role. To estimate their magnitude, we compare a semiclassical simulation based on the solution of Poisson's equation with a quantum computation solving the complete system of Schrodinger's and Poisson's equation. Despite the three-dimensional nature of the problem, a two-dimensional computational mesh proved to be sufficient to provide good agreement with experimental results, after three-dimensional corrections were included. (C) 1998 American Institute of Physics. [S0021-8979(98)06221-5].