SINGLE-ELECTRON FLOATING-GATE MOS MEMORY

摘要

A Single Electron MOS Memory (SEMM), in which one bit of information is represented by storing only one electron, has been demonstrated at room temperature. The SEMM is a floating gate Metal-Oxide-Semiconductor (MOS) transistor in silicon with a channel width (about 10 nanometers) which is smaller than the Debye screening length of a single electron stored on the floating gate (26), and a nonoscale polysilicon dot (about 7 nanometers by nanometers by 2 nanometers) as the floating gate which is positioned between the channel and the control gate (30). An electron stored on the floating gate (26) can screen the entire channel from the potential on the control gate, and lead to: (i) a discrete shift in the threshold voltage; (ii) a staircase relation between the charge voltage and the shift; and (iii) a self-limiting charge process. The structure and fabrication of the SEMM is well adapted to the manufacture of ultra large-scale integrated circuits.