Semiconductor memory structure having enhanced memory window and method for manufacturing the same

A semiconductor device comprising:

• a substrate;
• and
• a memory structure disposed over the substrate and including:
• a memory film having a first surface and a second surface opposite to the first surface,
• a plurality of conductive regions disposed on the first surface of the memory film, the conductive regions being spaced apart from each other in a first direction and extending in a second direction transverse to the first direction,
• a plurality of first conductive blocks disposed on the second surface of the memory film, the first conductive blocks being arranged in an array, which include a plurality of columns of the first conductive blocks spaced apart from each other in the first direction, the first conductive blocks in each column being spaced apart from each other in the second direction,
• a plurality of second conductive blocks disposed on the second surface of the memory film, the second conductive blocks being arranged in an array, which include a plurality of columns of the second conductive blocks spaced apart from each other in the first direction, the second conductive blocks in each column being spaced apart from each other in the second direction, the plurality of columns of the second conductive blocks being disposed to alternate with and separate from the plurality of columns of the first conductive blocks, and
• a plurality of third conductive blocks disposed on the second surface of the memory film, the third conductive blocks being arranged in an array, which includes a plurality of columns of the third conductive blocks spaced apart from each other in the first direction, the third conductive blocks in each column being spaced apart from each other in the second direction, each column of the third conductive blocks being disposed between and spaced apart from a corresponding column of the first conductive blocks and a corresponding column of the second conductive blocks in the first direction, each of the third conductive blocks being disposed between and spaced apart from a corresponding one of the first conductive blocks and a corresponding one of the second conductive blocks in the first direction.

A method for manufacturing a semiconductor device, comprising:

• forming a memory film over a substrate;
• forming a plurality of conductive regions on a first surface of the memory film, such that the conductive regions is spaced apart from each other in a first direction and extend in a second direction transverse to the first direction;
• forming a plurality of first conductive blocks on a second surface of the memory film, such that the first conductive blocks are arranged in an array, which include a plurality of columns of the first conductive blocks spaced apart from each other in the first direction, the first conductive blocks in each column being spaced apart from each other in the second direction;
• forming a plurality of second conductive blocks on the second surface of the memory film, such that the second conductive blocks are arranged in an array, which include a plurality of columns of the second conductive blocks spaced apart from each other in the first direction, the second conductive blocks in each column being spaced apart from each other in the second direction, the plurality of columns of the second conductive blocks being disposed to alternate with and separate from the plurality of columns of the first conductive blocks;
• and
• forming a plurality of third conductive blocks on the second surface of the memory film, such that the third conductive blocks are arranged in an array, which includes a plurality of columns of the third conductive blocks spaced apart from each other in the first direction, the third conductive blocks in each column being spaced apart from each other in the second direction, each column of the third conductive blocks being disposed between and spaced apart from a corresponding column of the first conductive blocks and a corresponding column of the second conductive blocks in the first direction, each of the third conductive blocks being disposed between and spaced apart from a corresponding one of the first conductive blocks and a corresponding one of the second conductive blocks in the first direction.