Method and apparatus providing multi-planed array memory device
A three-dimensional variable resistance memory array and method of forming the same. The memory array has memory cells in multiple planes in three dimensions. The planes of the memory cells include shared interconnect lines, dually connected to driving and sensing circuits, that are used for addressing the cells for programming and reading. The memory array is formed using only a single patterned mask per central array plane to form the memory cells of such planes.
1. A memory cell, comprising:
a phase change element of a plane of phase change material in series with a diode, the plane of phase change material comprising a plurality of memory cells that include the memory cell;
a first electrode line coupled with the diode opposite the phase change element; and
a second electrode line coupled with the phase change element opposite the diode,
wherein each of the first electrode line and second electrode line is respectively coupled with a driver circuit and a sense circuit and at least one of the first electrode line and second electrode line is shared with another memory cell.
2. The memory cell of claim 1 , wherein the first electrode line and the second electrode line are arranged in a cross point architecture.
3. The memory cell of claim 1 , wherein the first electrode line and the second electrode line are respectively coupled with the driver circuit and the sense circuit by respective access devices.
4. The memory cell of claim 3 , wherein the respective access devices comprise a gated transistor, or a select gate, or a combination thereof.
5. The memory cell of claim 1 , wherein the driver circuit and sense circuit are respectively coupled with different terminal ends of the first electrode line and with different terminal ends of the second electrode line.
6. The memory cell of claim 1 , wherein the driver circuit and sense circuit are respectively coupled with same terminal ends of the first electrode line and with same terminal ends of the second electrode line.
7. The memory cell of claim 1 , wherein the memory cell is part of a three-dimensional memory array, and wherein the memory cell is addressed by an X, a Y, and a Z address coordinate.
8. A memory device, comprising:
a memory array comprising:
a plane of phase change material comprising a plurality of memory cells; and
a plurality of electrode line levels, wherein memory cells of the plurality of memory cells are located between each electrode line level of the plurality of electrode line levels;
a set of write access devices coupled with each electrode line level of the plurality of electrode line levels;
a set of sense access devices coupled with each electrode line level of the plurality of electrode line levels; and
circuitry coupled with the set of write access devices and the set of sense access devices, the circuitry configured to access memory cells of the plurality.
9. The memory device of claim 8 , wherein the memory device is configured to select one or more electrode line levels of the plurality of electrode line levels to program a target memory cell, the target memory cell comprising a phase change memory element of the plane of phase change material and a diode.
10. The memory device of claim 9 , wherein the set of write access devices or the set of sense access devices is configured to apply a current pulse to the selected one or more electrode line levels, the current pulse biasing the diode of the target memory cell with a forward bias current.
11. The memory device of claim 10 , wherein the current pulse provides a programming current in the phase change memory element of the target memory cell.
12. The memory device of claim 9 , wherein the memory device is configured to float unselected electrode line levels of the plurality of electrode line levels concurrent with programming the target memory cell.
13. The memory device of claim 8 , wherein the memory array comprises a three-dimensional memory array, and wherein memory cells of the plurality are addressed by a three-dimensional address coordinate.