Title :
Program Trapped-Charge Effect on Random Telegraph-Noise Amplitude in a Planar SONOS Flash Memory Cell
Author :
Ma, H.C. ; Chou, Y.L. ; Chiu, J.P. ; Wang, Tahui ; Ku, S.H. ; Zou, N.K. ; Chen, Vincent ; Lu, W.P. ; Chen, K.C. ; Lu, Chih-Yuan
Author_Institution :
Dept. of Electron. Eng., Nat. Chiao Tung Univ., Hsinchu, Taiwan
Abstract :
Program-charge effects in a SONOS Flash cell on the amplitude of random telegraph noise (RTN) are investigated. We measure RTN in 45 planar SONOS cells and 40 floating-gate (FG) cells in erase state and program state, respectively. We find that a SONOS cell has a wide spread in RTN amplitudes after programming, while an FG cell has identical RTN amplitudes in erase and program states at the same read-current level. A 3-D atomistic simulation is performed to calculate RTN amplitudes. Our result shows that the wide spread of program-state RTN amplitudes in a SONOS cell is attributed to a current-path-percolation effect caused by random discrete nitride charges.
Keywords :
circuit noise; circuit simulation; flash memories; telegraphy; 3-D atomistic simulation; current-path-percolation effect; erase state; floating-gate cells; planar SONOS flash memory cell; program state; program trapped-charge effect; random discrete nitride charges; random telegraph-noise amplitude; read-current level; Percolation; SONOS; program charge; random telegraph noise (RTN);
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2009.2030589
