Room Temperature Single-Electron Narrow-Channel Memory with Silicon Nanodots Embedded in SiO2 Matrix

Abstract
The room-temperature operation of a single-electron narrow-channel memory device has been demonstrated by the combined fabrication of a narrow-channel (20 nm wide by 80 nm long) field-effect transistor (FET) defined by electron-beam lithography and nanocrystalline Si (nc-Si) dots formed by annealing a thin film of SiO x (x<2). Electrons are injected into nc-Si floating gate dots in discrete units, as observed by the stepwise increase in the threshold shift with writing bias, which is expected for Coulomb repulsion within the nc-Si dot. Time-dependent measurement of the channel current under the floating gate shows stepwise loss of charge, with a lifetime of each stored electron of about 500 s at room temperature. Measurements at low temperature (20 K) show similar discrete steps in memory writing.