Patent ID: 8349688

Claim:
A method for manufacturing a nonvolatile semiconductor memory including a floating gate arranged so as to surround an outer periphery of an island-shaped semiconductor with a tunnel insulating film interposed between the floating gate and the island-shaped semiconductor, a control gate arranged so as to surround an outer periphery of the floating gate with a second insulating film interposed between the control gate and the floating gate, and a control gate line electrically connected to the control gate and extending in a predetermined direction, the method comprising: a step of forming a plurality of island-shaped semiconductors on a source line formed at a predetermined position on a substrate; a step of forming a first insulating film between the island-shaped semiconductors that are adjacent to each other and on the source line; a step of forming a floating gate film by depositing a conductive material on the first insulating film; a step of forming a resist on the floating gate film, the resist having a groove extending in a direction perpendicular to the predetermined direction in which the control gate line extends; a step of forming a floating gate for each of the island-shaped semiconductors using the resist by separating the floating gate film from a portion that is a lower region of the groove and that is on the first insulating film by etching; a step of forming the second insulating film on the floating gate; a step of forming, on the second insulating film, a control gate that surrounds an outer periphery of each of the island-shaped semiconductors; a step of forming the control gate line connecting the control gates of adjacent island-shaped semiconductors among the island-shaped semiconductors; and a step of etching the floating gates so that the control gates and the floating gates overlap one another in a vertical direction with the second insulating film therebetween.