Patent ID: 8445349
Filing Date: 2013-05-21
Classification: H01L

Abstract:
1. A method of manufacturing a nonvolatile semiconductor memory device, the method comprising: forming a plurality of memory cell transistors and a plurality of selection transistors on a substrate; burying first and second insulators successively between memory cell transistors and between a memory cell transistor and a selection transistor, and forming the first and second insulators successively on side surfaces of selection transistors, the side surfaces facing a space between the selection transistors; burying third, fourth and fifth insulators successively between the selection transistors via the first and second insulators; removing all the second and fourth insulators by a first etching so that the second and fourth insulators partially remain between the selection transistors; and removing the second and fourth insulators remaining between the selection transistors by a second etching performed after the first etching.