Method of manufacturing flash memory device

A method of manufacturing a flash memory device, comprising the steps of:

• providing a semiconductor substrate in which a cell region and a peri region are defined;
• forming a floating gate pattern by laminating a tunnel oxide film, a first conductive layer, and a nitride film on the semiconductor substrate of a first region, and forming isolation films on the semiconductor substrate of a second region;
• stripping the nitride film, blocking the peri region, and then etching the isolation films of the cell region to a predetermined thickness by a dry etch process;
• and
• sequentially forming a dielectric film, a second conductive layer, and a hard mask film on the entire structure, patterning the hard mask film to form a control gate, and etching the floating gate pattern using the control gate as a mask, thus forming a floating gate.

A method of manufacturing a flash memory device, comprising the steps of:

• providing a semiconductor substrate in which a cell region and a peri region are defined;
• sequentially laminating a tunnel oxide film, a first conductive layer, and a nitride film on the semiconductor substrate of a first region and forming isolation films the semiconductor substrate of a second region;
• stripping the nitride film, blocking the peri region, and then etching the isolation films of the cell region to a predetermined thickness by a dry etch process;
• forming second conductive layer on the first conductive layer in such a way to be partially overlapped with the isolation films, forming a floating gate pattern;
• and
• sequentially forming a dielectric film, a second conductive layer, and a hard mask film on the entire structure, patterning the hard mask film to form a control gate, and etching the floating gate pattern using the control gate as a mask, thus forming a floating gate.