Patent ID: 7276415
Filing Date: 2007-10-02
Classification: H01L

Abstract:
1. A method of forming a contactless nonvolatile memory device, the method comprising: preparing a semiconductor substrate including a cell array region; forming a plurality of mask patterns being parallel to each other on the semiconductor substrate in the cell array region; etching the semiconductor substrate using the plurality of mask patterns as an etch mask to form a plurality of recess regions; forming a gate insulating layer on sidewalls and bottoms of the plurality of recess regions; forming a floating gate layer on an upper surface of the semiconductor substrate to fill the plurality of recess regions; planarizing the floating gate layer to expose upper surfaces of the plurality of mask patterns and to respectively form floating gate patterns in the plurality recess regions; forming buried impurity diffusion regions in the semiconductor substrate under the plurality of mask patterns; forming an intergate dielectric layer; forming a control gate layer; and patterning the control gate layer, the intergate dielectric layer and the floating gate pattern to form a plurality of parallel word lines respectively crossing the plurality of mask patterns, floating gates between the plurality of parallel word lines and the recess regions, and an intergate dielectric pattern between the floating gates and the plurality of parallel word lines, and to expose the plurality of recess regions and the plurality of mask patterns between plurality of parallel word lines.