EEPROM cell with trench coupling capacitor

摘要

An embodiment of the memory cell for an EEPROM device may comprise a trench coupling capacitor wherein the coupling oxide of the coupling capacitor is formed only in the trench (i.e., such that coupling occurs only in the trench). In addition, a first portion of a floating gate of the memory cell is formed in the trench to function as a part of the coupling capacitor as well as a floating gate. A floating gate second portion is electrically connected to the first portion. A control gate is connected to a doped region of the substrate and a thin tunnel dielectric physically separates the floating gate second portion from the coupling oxide layer and from the doped region of the substrate.