Method of manufacturing memory having 3-dimensional structure

PURPOSE: A method for manufacturing memory with a three dimensional structure is provided to make a non-volatile memory device with the high degree of integration by making a three dimensional structure and forming a plurality of cell transistors in a multil active layer. CONSTITUTION: A pre-etching film and an insulating film are alternately formed. A selection insulating layer(316), a selection etching film, and a sacrificial insulating film(318) are successively formed in the upper part of the pre-etch film which is a top layer. Multi active layers(330), which are arranged into a first direction, are formed passing through the pre-etching film, the insulating layer, the selection insulating layer, the selection etching film, and the sacrificial insulating film. A cell area, in which a contact area and the multi active layers are formed, is defined. The level difference of a second direction which is vertical to the first direction is formed by the imprint of a pattern in a contact area. A plurality of string areas, which is extended toward the first direction, is formed by selectively etching the cell area after the imprint of the pattern. The selection etching film and the pre-etch film are eliminated. An ONO(Oxide-Nitride-Oxide) layer and a conductive film are formed on the side of the multi active layers.