High density nonvolatile memory cell unit array
In a memory cell unit array, memory cell units each constituted of first wires, second wires, and a nonvolatile memory cell are arranged in a two-dimensional matrix form in a first direction and a second direction. Each of the memory cell units includes a control circuit below it. The control circuit is constituted of a first control circuit and a second control circuit. The second wires are connected to the second control circuit. Some of the first wires that constitute the memory cell unit are connected to the first control circuit that constitutes this memory cell unit. Others of the first wires are connected to the first control circuit that constitutes an adjacent memory cell unit adjacent thereto in the first direction.
1. A memory cell unit array, comprising
memory cell units arranged in a two-dimensional matrix form in a first direction and a second direction, the memory cell units being each constituted of
a plurality of first wires extending in the first direction,
a plurality of second wires that are disposed separately from the first wires in upper and lower directions and extend in the second direction unlike the first wires, and
a nonvolatile memory cell that is disposed in a region in which the first wires and the second wires overlap one another and connected to the first wires and the second wires, wherein
each of the memory cell units includes, below the memory cell unit, a control circuit that controls an operation of the memory cell unit,
the control circuit is constituted of
a first control circuit that controls an operation of the nonvolatile memory cell that constitutes the memory cell unit via the first wires, and
a second control circuit that controls an operation of the nonvolatile memory cell that constitutes the memory cell unit via the second wires,
the second wires that constitute the memory cell unit are connected to the second control circuit that constitutes the memory cell unit,
some of the first wires that constitute the memory cell unit are connected to the first control circuit that constitutes the memory cell unit, and
others of the first wires that constitute the memory cell unit are connected to a first control circuit that constitutes an adjacent memory cell unit adjacent thereto in the first direction.
2. The memory cell unit array according to claim 1 , wherein, in each of the memory cell units, the first wires connected to the first control circuit that constitutes the memory cell unit and the first wires connected to the first control circuit that constitutes the adjacent memory cell unit are alternately disposed.
3. The memory cell unit array according to claim 1 , wherein,
the control circuit is covered with an inter-layer insulating layer,
the first control circuit and the first wires are connected to one another via a first contact hole formed in the inter-layer insulating layer, and
the second control circuit and the second wires are connected to one another via a second contact hole formed in the inter-layer insulating layer.
4. The memory cell unit array according to claim 1 , wherein
the control circuit is covered with an inter-layer insulating layer,
the first control circuit and the first wires are connected to one another via a first control wire and a first contact hole formed in the inter-layer insulating layer,
the second control circuit and the second wires are connected to one another via a second control wire and a second contact hole formed in the inter-layer insulating layer,
the first control circuit and the second control wire do not overlap each other in the upper and lower directions, and
the second control circuit and the first control wire do not overlap each other in the upper and lower directions.
5. The memory cell unit array according to claim 3 , wherein
when the first contact hole in one of the memory cell units and the first contact hole in the memory cell unit adjacent to the one memory cell unit in the first direction are projected in a virtual perpendicular plane parallel to the second direction, positions of projection images of the first contact holes are positioned at equal intervals along the second direction.
6. The memory cell unit array according to claim 1 , wherein the second wires are, at end portions thereof, connected to the second control circuit.
7. The memory cell unit array according to claim 1 , wherein the memory cell units are arranged in-line along the second direction and arranged offset from each other along the first direction.
8. The memory cell unit array according to claim 7 , wherein the memory cell units are arranged in-line along the second direction and arranged offset from each other along the first direction by ½ of a length of the memory cell unit along the second direction.
9. The memory cell unit array according to claim 8 , wherein
half of the first wires that constitute the memory cell unit are connected to the first control circuit that constitutes the memory cell unit, and
the other half of the first wires that constitute the memory cell unit are connected to the first control circuit that constitutes the adjacent memory cell unit adjacent thereto in the first direction.
10. The memory cell unit array according to claim 1 , wherein the memory cell units are arranged in a stretcher bond pattern of brick patterns.
11. The memory cell unit array according to claim 10 , wherein
half of the first wires that constitute the memory cell unit are connected to the first control circuit that constitutes the memory cell unit, and
the other half of the first wires that constitute the memory cell unit are connected to the first control circuit that constitutes the adjacent memory cell unit adjacent thereto in the first direction.
12. The memory cell unit array according to claim 1 , wherein
the first control circuit is constituted of two circuits, a first(I) control circuit and a first(II) control circuit,
the second control circuit is constituted of two circuits, a second(I) control circuit and a second(II) control circuit,
the first(I) control circuit is disposed along a first side of the control circuit, which extends in parallel to the second direction,
the first(II) control circuit extends in parallel to the second direction and is disposed along a third side of the control circuit, which is opposed to the first side,
the second(I) control circuit is disposed along a second side of the control circuit, which extends in parallel to the first direction, and
the second(II) control circuit extends in parallel to the first direction and is disposed along a fourth side of the control circuit, which is opposed to the second side.
13. The memory cell unit array according to claim 12 , wherein
the second(I) control circuit is disposed to occupy the entire second side and occupy a part of the first side and a part of the third side,
the second(II) control circuit is disposed to occupy the entire fourth side and occupy a part of the first side and a part of the third side,
the first(I) control circuit is disposed to occupy a part of the first side, and
the first(II) control circuit is disposed to occupy a part of the third side.
14. The memory cell unit array according to claim 1 , wherein
the second control circuit is constituted of two circuits, a second(I) control circuit and a second(II) control circuit,
the second(I) control circuit is disposed along a second side of the control circuit, which extends in parallel to the first direction,
the second(II) control circuit extends in parallel to the first direction and is disposed along a fourth side of the control circuit, which is opposed to the second side, and
the first control circuit is disposed to extend from a first side of the control circuit, which extends in parallel to the second direction, to a third side of the control circuit, which is opposed to the first side.
15. The memory cell unit array according to claim 1 , wherein
the first control circuit is constituted of two circuits, a first(I) control circuit and a first(II) control circuit,
the second control circuit is disposed to extend from a second side of the control circuit, which extends in parallel to the first direction, to a fourth side of the control circuit, which is opposed to the second side,
the first(I) control circuit is disposed along a first side of the control circuit, which extends in parallel to the second direction, and
the first(II) control circuit extends in parallel to the first direction and is disposed along a third side of the control circuit, which is opposed to the first side.
16. The memory cell unit array according to claim 1 , wherein the nonvolatile memory cell is multi-layered having N layers (where N≥2).
17. The memory cell unit array according to claim 16 , wherein
the first wires are formed in first wire layers that are N layers,
the second wires are formed in second wire layers that are N layers, and
the nonvolatile memory cell is formed between the first wire layer and the second wire layer.
18. The memory cell unit array according to claim 16 , wherein
the first wires are formed in first wire layers that are (N/2+1) layers (where N is an even number equal to two or more),
the second wires are formed in a second wire layer that is (N/2) layer, and
the nonvolatile memory cell is formed between the first wire layer and the second wire layer.
19. The memory cell unit array according to claim 16 , wherein
the first wires are formed in a first wire layer that is (N/2) layer (where N is an even number equal to two or more),
the second wires are formed in second wire layers that are (N/2+1) layers, and
the nonvolatile memory cell is formed between the first wire layer and the second wire layer.
20. The memory cell unit array according to claim 16 , wherein
the first wires are formed in first wire layers that are {(N+1)/2} layers (where N is an odd number equal to three or more),
the second wires are formed in second wire layers that are {(N+1)/2} layers, and
the nonvolatile memory cell is formed between the first wire layer and the second wire layer.