| 摘要 |
Floating gate structures are disclosed which have a base field coupled with the substrate and a narrow projection extending from the base away from the substrate. In one form, surfaces of a relatively large projection provide an increased surface area for a control gate that wraps around it, thereby increasing the coupling between the two. In another form, an erase gate wraps around a relatively small projection in order to take advantage of sharp edges of the projection to promote tunneling of electrons from the floating to the erase gate. In each case, the control or floating gate is positioned within the area of the floating gate in one direction, thereby not requiring additional substrate area for such memory cells. |
