Vertical cross-point memory arrays
A method of manufacturing a memory structure includes forming a plurality of vertically-stacked horizontal line layers, interleaving a plurality of electrically conductive vertical lines with the electrically conductive horizontal lines, and forming a memory film at and between intersections of the electrically conductive vertical lines and the horizontal lines. In one embodiment of the invention, the electrically conductive vertical lines are interleaved with the horizontal lines such that a row of vertical lines is positioned between each horizontally-adjacent pair of horizontal lines in each horizontal line layer. By configuring the electrically conductive vertical lines and electrically conductive horizontal lines so that a row of vertical lines is positioned between each horizontally-adjacent pair of horizontal lines, a unit memory cell footprint of just 2F 2 may be realized.
1. A vertical cross-point array structure comprising:
a plurality of vertically-stacked layers of electrically conductive horizontal lines, the plurality of vertically-stacked layers of electrically conductive horizontal lines being separated by a dielectric material, and the plurality of electrically conductive horizontal lines comprising a first plurality of electrodes;
a plurality of electrically conductive vertical lines interleaved with the plurality of electrically conductive horizontal lines, the plurality of electrically conductive vertical lines extending through holes in the dielectric material, wherein the holes are lined with one or more memory films, and the plurality of electrically conductive vertical lines comprising a second plurality of electrodes; and
an array of vertically-stacked two-terminal memory elements formed between the first plurality of electrodes and the second plurality of electrodes.
2. The vertical cross-point array structure of claim 1 , wherein the one or more memory films comprise one or more resistive change memory films deposited on sidewalls of the holes.
3. The vertical cross-point array structure of claim 1 , wherein the one or memory films on comprise an insulating metal oxide (IMO) film and a conductive metal oxide (CMO) film deposited on sidewalls of the holes.
4. The vertical cross-point array structure of claim 3 , wherein the IMO film has a thickness between about 5 and 50 Angstroms and the CMO film has a thickness between about 15 and 300 Angstroms.
5. The vertical cross-point array structure of claim 1 , wherein at least one of the second plurality of electrodes is positioned between every horizontally-adjacent pair of electrically conductive horizontal lines in each layer of electrically conductive horizontal lines.
6. The vertical cross-point array structure of claim 1 , wherein at least one of the second plurality of electrodes is positioned between only every other horizontally-adjacent pair of electrically conductive horizontal lines in each layer of electrically conductive horizontal lines.
7. The vertical cross-point array structure of claim 1 , further comprising:
a first set of global bit lines below the array of vertically-stacked two-terminal memory elements, wherein each one of the first set of global bit lines is electrically connected to a first subset of alternate ones of the electrically conductive vertical lines.
8. The vertical cross-point array structure of claim 7 , further comprising:
a second set of global bit lines above the array of vertically-stacked two-terminal memory elements, wherein each one of the second set of global bit lines is electrically connected to a second subset of alternate ones of the electrically conductive vertical lines, wherein the first and second subsets are mutually exclusive.
9. An electronic device comprising:
a plurality of vertically-stacked layers of electrically conductive horizontal lines, the plurality of vertically-stacked layers of electrically conductive horizontal lines being separated by a dielectric material, and the plurality of electrically conductive horizontal lines comprising a first plurality of electrodes;
a plurality of electrically conductive vertical lines interleaved with the plurality of electrically conductive horizontal lines, the plurality of electrically conductive vertical lines extending through holes in the dielectric material, wherein the holes are lined with one or more memory films, and the plurality of electrically conductive vertical lines comprising a second plurality of electrodes;
an array of vertically-stacked two-terminal memory elements formed between the first plurality of electrodes and the second plurality of electrodes;
a first set of global bit lines below the array of vertically-stacked two-terminal memory elements, wherein each one of the first set of global bit lines is electrically connected to a first subset of alternate ones of the electrically conductive vertical lines; and
a second set of global bit lines above the array of vertically-stacked two-terminal memory elements, wherein each one of the second set of global bit lines is electrically connected to a second subset of alternate ones of the electrically conductive vertical lines, wherein the first and second subsets are mutually exclusive.
10. The electronic device of claim 9 , wherein the one or more memory films comprise one or more resistive change memory films deposited on sidewalls of the holes.
11. The electronic device of claim 9 , wherein the one or memory films on comprise an insulating metal oxide (IMO) film and a conductive metal oxide (CMO) film deposited on sidewalls of the holes.
12. The electronic device of claim 11 , wherein the IMO film has a thickness between about 5 and 50 Angstroms and the CMO film has a thickness between about 15and 300 Angstroms.
13. The electronic device of claim 9 , wherein at least one of the second plurality of electrodes is positioned between every horizontally-adjacent pair of electrically conductive horizontal lines in each layer of electrically conductive horizontal lines.
14. The electronic device of claim 9 , wherein at least one of the second plurality of electrodes is positioned between only every other horizontally-adjacent pair of electrically conductive horizontal lines in each layer of electrically conductive horizontal lines.
15. The electronic device of claim 9 , wherein each of the plurality of electrically conductive vertical lines is disposed to serve as a shared bit line for accessing memory elements facing left with respect to a centerline of the respective electrically conductive vertical line and also as a shared bit line for accessing memory elements facing right with respect to the centerline of the respective electrically conductive vertical line.
16. The electronic device of claim 15 , wherein each electrically conductive horizontal line is disposed to serve as a shared word line for the memory elements formed between the electrically conductive horizontal line and each electrically conductive vertical line that the electrically conductive horizontal line crosses, including at each such crossing, the left facing memory cell and the right facing memory cell, whereby the electrically conductive horizontal line accesses two rows of memory cells.
17. The electronic device of claim 9 , further comprising:
a first set of selection devices below the array of vertically-stacked two-terminal memory elements, the first set of selection devices operable to selectively electrically couple a first subset of alternate ones of the electrically conductive vertical lines to the first set of global bit lines.
18. The electronic device of claim 17 , further comprising:
a second set of selection devices above the array of vertically-stacked two-terminal memory elements, the second set of selection devices operable to selectively electrically couple the second subset of the electrically conductive vertical lines to the second set of global bit lines.
19. The electronic device of claim 18 , further comprising:
an interconnect structure to electrically connect the first set and the second set of selection devices to the first set and the second set of global bit lines, respectively.
20. A memory apparatus comprising:
a plurality of vertically-stacked layers of electrically conductive horizontal lines, the plurality of vertically-stacked layers of electrically conductive horizontal lines being separated by a dielectric material, and the plurality of electrically conductive horizontal lines comprising a first plurality of electrodes;
a plurality of electrically conductive vertical lines interleaved with the plurality of electrically conductive horizontal lines, the plurality of electrically conductive vertical lines extending through holes in the dielectric material, wherein the holes are lined with a conductive metal oxide (CMO) film deposited on sidewalls of the holes, and the plurality of electrically conductive vertical lines comprising a second plurality of electrodes; and
an array of vertically-stacked two-terminal memory elements formed between the first plurality of electrodes and the second plurality of electrodes.