Gate-all-around single silicon nanowire MOSFET with 7 nm width for SONOS NAND flash memory

Gate-all-around (GAA) MOSFET with single silicon nanowire is fabricated and applied to SONOS memory as a cell transistor for NAND flash string. Driving current over 1 uA, which is sufficient to NAND string, is obtained with single nanowire of ~7 nm width. Using FN tunneling conditions, V_TH window of 4.5 V and fast program/erase (P/E) speed of ~10 us are obtained, respectively. The smaller nanowire width is, the faster program speed and the larger V_TH shift are achieved. P/E operations in NAND string with GAA SONOS nanowire are demonstrated for the first time.