Method of manufacturing nonvolatile memory device

Abstract

A method of manufacturing a nonvolatile memory device is disclosed. The method includes the steps of forming a tunnel oxide layer, a first conductive layer for a floating gate, and a hard mask layer over a semiconductor substrate, etching a portion of the hard mask layer, the first conductive layer, the tunnel oxide layer and the semiconductor substrate, forming trenches, gap-filling the trenches with an insulating material to form isolation layers, removing the hard mask layer, forming second conductive layer for a floating gate on the entire surface, forming spacers on vertical faces of the second conductive layer, removing the second conductive layer on the isolation layers and between the spacers by means of an etch process using the spacers as etch masks, removing the spacers, and forming a dielectric layer and a third conductive layer on the entire surface including the second conductive layer. The method reduces the interference capacitance between neighboring word lines, minimizes the interference phenomenon, and minimizes the distributions of the program threshold voltage Vth between word lines.