| 摘要 |
A non-volatile memory cell is made in a substrate of a substantially single crystalline semiconductive material having a first conductivity type and a surface. A trench is in the surface and extends into the substrate to a first depth and to a second depth, which is deeper than the first depth. The trench has a first sidewall along the trench extending to the first depth, and a second sidewall along the trench extending from the first depth to the second depth, and a bottom wall along the bottom of the trench. A first region of a second conductivity type is in the substrate, along the bottom of the trench. A second region of the second conductivity type is in the substrate, along the surface of the trench. A channel region is in the substrate between the first region and the second region; the channel region has a first portion and a second portion, with the first portion between the surface and the first depth and is along the first sidewall. The second portion of the channel region is between the first depth and the second depth and is along the second sidewall. A control gate extends from the surface of the substrate into the trench to the second depth, insulated from the bottom. The control gate is adjacent to and insulated from the second sidewall of the trench. A floating gate is adjacent to and insulated from the first sidewall of the trench, between the first sidewall of the trench and the control gate.
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