Method of programming a semiconductor memory device

摘要

A programmable EEPROM cell structure consisting in a split-gate structure in series with a coupling capacitor between the floating gate (16) and an additional program gate (19) in order to provide enhanced injection efficiency. The electron injection is controlled by a control gate (17) at the source side. The area of the coupling capacitor is selected with a substantial coupling factor to apply a high voltage to the floating gate (16) during programming so as to produce hot-electron injection at the split point in the channel region between the control gate (17) and the floating gate (16). Submicrosecond programming at a drain voltage not greater than 5 V can thereby be achieved. <IMAGE>