NONVOLATILE SEMICONDUCTOR STORAGE DEVICE AND MANUFACTURING METHOD THEREOF

摘要

PROBLEM TO BE SOLVED: To improve burying properties of an interlayer insulating film and a metal film in a space between memory cells while making the space narrower. SOLUTION: Prepared is a semiconductor substrate 10 where memory cell precursors each including ONO films 52L and 52R stacked on gate electrodes 14L and 14R facing each other and an ion injection protection film covering a primary surface 10a between the gate electrodes are provided on the primary surface at intervals of a first distance, and a manufacturing method includes a step of changing the distance between the memory precursors to a second distance longer than the first distance by reducing thicknesses of second oxide films 32L and 32R measured at right angles to side surfaces 14LS and 14RS through wet etching. COPYRIGHT: (C)2009,JPO&INPIT