| abstract |
The preparation method and structure of a three-dimensional memory provided by the present invention change the ONOP process to the AONOP process, that is, after etching the conductive channel in the array storage area, aluminum oxide and silicon dioxide are respectively prepared by atomic layer deposition. , silicon nitride, silicon dioxide, and polysilicon stacks, so that atomic layer deposition of aluminum oxide is no longer required after dummy gate wet removal. The thickness of the tungsten metal gate in the three-dimensional memory is increased, the resistance of the metal gate is reduced, and the selection ratio difficulty of etching the tungsten contact hole in the step area is reduced. |