Charging and retention times in silicon-floating-dot-single-electron memory

The mechanism of electron storage was studied in a metal- oxide-silicon (MOS)-type single-electron memory which utilized the direct tunneling of electrons between a silicon floating dot and the conducting channel on the surface of silicon substrate. Time constants of charging and discharging were derived by a simple analysis of a single-electron box circuit, taking the structure of the energy band of silicon into consideration. It was shown that the features of the energy band were substantial for the memory function of the device and that a write time of the order of sub-microseconds was obtained; 10(10) times longer retention time was also obtained with compatibility in the same device at room temperature.