Impact of reactive ion etching using O/sub 2/+CHF/sub 3/ plasma on the endurance performance of FLOTOX EEPROM cells

The influence of the reactive ion etching (RIE) process step performed with O/sub 2/+CHF/sub 3/ plasma on the endurance performance of FLOTOX EEPROM cells is investigated. The comparison with the standard wet etching procedure (WEP) shows that the observed higher programming window degradation Delta W/sub p/ as well as the unbalanced high-to-low state threshold-voltage shifts can be quantitatively attributed to the fluorine (F) contamination of the tunnel oxide layer near the floating gate (FG) electrode. >