Thermally optimized phase change memory cells and methods of fabricating the same
A thermally optimized phase change memory cell includes a phase change material element disposed between first and second electrodes. The second electrode includes a thermally insulating region having a first thermal resistivity over the first electrode and a metallic contact region interposed between the phase change material element and the thermally insulating region, where the metallic contact layer has a second thermal resistivity lower than the first thermal resistivity.
1. A memory element, comprising:
a first electrode;
a chalcogenide material element located on the first electrode, wherein the chalcogenide material element comprises a selector node;
a second electrode disposed on the chalcogenide material element and comprising a thermally insulating carbon region and a metallic contact region located between the chalcogenide material element and the thermally insulating carbon region; and
a metallic access line coupled with the thermally insulating carbon region.
2. The memory element of claim 1 , wherein the thermally insulating carbon region is associated with a thermal resistivity different from the metallic contact region.
3. The memory element of claim 1 , wherein:
the thermally insulating carbon region is associated with a first thermal resistivity; and
the metallic contact region is associated with a second thermal resistivity lower than the first thermal resistivity.
4. The memory element of claim 1 , further comprising:
a storage node that is electrically coupled to the selector node via the first electrode.
5. The memory element of claim 1 , wherein a resistance of a portion of the chalcogenide material element is greater than a combined resistance of a portion of the thermally insulating carbon region, a portion of the metallic contact region, and an interface between the metallic contact region and the chalcogenide material element.
6. The memory element of claim 1 , wherein the metallic access line is coupled with the memory element and a second memory element.
7. The memory element of claim 6 , further comprising:
a sidewall insulator located between the memory element and the second memory element, wherein the sidewall insulator comprises at least two layers.
8. The memory element of claim 7 , wherein the at least two layers comprise:
a first layer adjacent to the memory element; and
a second layer located between the first layer and the second memory element.
9. The memory element of claim 8 , wherein the first layer comprises a material composition different from the second layer.
10. A device comprising:
a first electrode;
a chalcogenide material element located on the first electrode, wherein the chalcogenide material element comprises a selector node of a memory cell;
a second electrode disposed on the chalcogenide material element, wherein the second electrode comprises a thermally insulating carbon region and a metallic contact region between the chalcogenide material element and the thermally insulating carbon region; and
a sidewall insulator in contact with each of the first electrode, the chalcogenide material element, and the second electrode.
11. The device of claim 10 , wherein the thermally insulating carbon region has a first thermal resistivity higher than a second thermal resistivity of the metallic contact region.
12. The device of claim 10 , wherein the first electrode is configured to electrically couple a storage node to the selector node.
13. The device of claim 10 , wherein the sidewall insulator comprises a plurality of insulating layers.
14. The device of claim 10 , wherein the sidewall insulator is adjacent to the selector node.
15. A device comprising:
a first electrode;
a chalcogenide material element located on the first electrode;
a second electrode located on the chalcogenide material element; and
an access line extending in a first direction, wherein the access line and the second electrode have a same nominal width in a second direction different from the first direction.
16. The device of claim 15 , wherein the second electrode comprises a thermally insulating region and a metallic contact region located between the chalcogenide material element and the thermally insulating region.
17. The device of claim 16 , wherein:
the thermally insulating region comprises carbon and is associated with a first thermal resistivity; and
the metallic contact region is associated with a second thermal resistivity lower than the first thermal resistivity.
18. The device of claim 16 , further comprising:
a sidewall insulator adjacent to each of the first electrode, the chalcogenide material element, and the second electrode.
19. The device of claim 15 , wherein the access line is in contact with the second electrode and extends in the first direction.
20. The device of claim 15 , wherein the second direction is perpendicular to the first direction.