On the origin of the dispersion of erased threshold voltages in flash EEPROM memory cells

Citation
D. Esseni et B. Ricco, On the origin of the dispersion of erased threshold voltages in flash EEPROM memory cells, IEEE DEVICE, 47(5), 2000, pp. 1120-1123
Citations number
11
Categorie Soggetti
Eletrical & Eletronics Engineeing
Journal title
IEEE TRANSACTIONS ON ELECTRON DEVICES
ISSN journal
00189383 → ACNP
Volume
47
Issue
5
Year of publication
2000
Pages
1120 - 1123
Database
ISI
SICI code
0018-9383(200005)47:5<1120:OTOOTD>2.0.ZU;2-E
Abstract
This work investigates the origin of the dispersion of tunnel-erased thresh old voltages (V-T) in flash EEPROM memory cells. A clear correlation betwee n cell-to-cell variations of tunnel current I-T. and dispersion of erased V -T is demonstrated by looking at the I-T characteristics and the erasing ch aracteristics corresponding to channel and source injection as well as at t he dependence of I-T and V-T dispersion on device area and tunnel polarity. Experimental evidence is provided that nonuniform injection at polySi/SiO2 interface is a major cause of erased V-T dispersion.