Patent ID: 6051465
Filing Date: 2000-04-18
Classification: H01L

Abstract:
A method for fabricating a nonvolatile semiconductor memory device, comprising the steps of:forming a first mask to define a channel of a memory cell in a semiconductor substrate;doping an impurity into the semiconductor substrate by using the first mask, thereby forming a first doped region in the semiconductor substrate;forming a second mask so as to overlap at least one of a first region of the semiconductor substrate where a source is to be formed and a second region of the semiconductor substrate where a drain is to be formed and at least part of the first mask;etching the semiconductor substrate by using the first and second masks, thereby forming a recessed portion in a region of the semiconductor substrate that is not covered with the first and second masks;forming a second doped region in the recessed portion of the semiconductor substrate; andremoving the first and second masks, and forming a gate structure including a first insulating film, a floating gate electrode, a second insulating film and a control gate electrode at least over a side surface of the recessed portion and the channel defined by the first mask.