Title :
Edge Profile Effect of Tunnel Oxide on Erase Threshold-Voltage Distributions in Flash Memory Cells
Author :
Kim, Bomsoo ; Kwon, Wook-Hyun ; Baek, Chang-Ki ; Son, Younghwan ; Park, Chan-Kwang ; Kim, Kinam ; Kim, Dae M.
Author_Institution :
Sch. of Comput. Sci., Korea Inst. for Adv. Study, Seoul
Abstract :
The erase threshold-voltage (VT) distribution in Flash electrically erasable programmable read-only memory cells was investigated versus the tunnel oxide edge profiles in self-aligned shallow trench isolation (SA-STI) and self-aligned poly (SAP) cells. The capacitive coupling with offset voltage correction is transcribed into VT transient for simulating erase VT dispersion without numerous full structure device simulations. It is shown that SAP gives rise to smaller VT dispersion, compared with SA-STI. The VT dispersion resulting from variations in dielectric thickness and oxide edge profiles is shown to fall far short of observed VT distribution, calling for examination of additional process and cell parameters
Keywords :
EPROM; coupled circuits; EEPROM; capacitive coupling equation; edge profile effect; electrically erasable programmable read-only memory cell; erase threshold voltage distributions; flash memory cells; offset voltage; self aligned shallow trench isolation; self-aligned poly cells; tunnel oxide; Dielectrics; Difference equations; Differential equations; Dispersion; EPROM; Flash memory cells; Geometry; PROM; Threshold voltage; Tunneling; Capacitive coupling equation with offset voltage; Flash electrically erasable programmable read-only memory (EEPROM) cell; edge profile effect; erase threshold voltage distribution;
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2006.885101
