Manufacture of flash memory device e.g. NAND type flash memory device, involves etching conductive layers and dielectric layers in single etch apparatus using hard mask layer as mask, where a control gate and a floating gate are formed

摘要

A flash memory device is manufactured by forming a dielectric layer, a third conductive layer, a fourth conductive layer and a hard mask layer and then patterning a hard mask layer; and etching from the fourth conductive layer to the first conductive layer in a single etch apparatus using the hard mask layer as a mask, where a control gate and a floating gate are formed. Manufacture of flash memory device involves: (1) forming tunnel oxide layer (203) and first conductive layer (204) on a semiconductor substrate (201) and then performing a shallow trench isolation process to form an isolation layer that defines a first region and a second region; (2) forming a second conductive layer (205) on the entire structure and then patterning the second conductive layer and the first conductive layer to form a floating gate pattern; (3) forming a dielectric layer (206), a third conductive layer (207), a fourth conductive layer (208) and a hard mask layer (209) on the entire structure and then patterning a hard mask layer; and (4) etching from the fourth conductive layer to the first conductive layer in a single etch apparatus using the hard mask layer as a mask, where a control gate and a floating gate are formed.