Film scheme to improve peeling in chalcogenide based PCRAM
Various embodiments of the present disclosure are directed towards a memory cell. The memory cell includes a bottom electrode overlying a substrate. A data storage structure overlies the bottom electrode. A top electrode overlies the data storage structure. Sidewalls of the top electrode and sidewall of the bottom electrode are aligned. Further, a getter layer abuts the bottom electrode.
1. A memory cell comprising:
a bottom electrode overlying a substrate;
a data storage structure overlying the bottom electrode;
a top electrode overlying the data storage structure, wherein sidewalls of the top electrode and sidewalls of the bottom electrode are aligned; and
a getter layer abutting the bottom electrode, wherein the getter layer is between the bottom electrode and the substrate.
2. The memory cell of claim 1 , wherein the getter layer comprises a conductive material configured to absorb an outgas species.
3. The memory cell of claim 1 , wherein the getter layer directly contacts the bottom electrode.
4. The memory cell of claim 1 , further comprising:
a conductive via underlying the bottom electrode; and
wherein the getter layer comprises the conductive via such that the getter layer and the conductive via comprise a single material.
5. The memory cell of claim 1 , wherein the getter layer comprises first grains and the bottom electrode comprises second grains larger than the first grains.
6. The memory cell of claim 1 , further comprising:
a middle electrode overlying the data storage structure; and
a second data storage structure between the middle electrode and the top electrode.
7. A memory device comprising:
a via overlying a substrate;
a first memory cell overlying the via, wherein the first memory cell comprises a top electrode, a bottom electrode, and a data storage structure disposed between the top and bottom electrodes, wherein sidewalls of the top electrode, sidewalls of the bottom electrode, and sidewalls of the data storage structure are aligned; and
a getter layer between the first memory cell and the via, wherein the getter layer contacts the bottom electrode.
8. The memory device of claim 7 , wherein sidewalls of the getter layer extend laterally past sidewalls of the first memory cell.
9. The memory device of claim 7 , further comprising:
a second memory cell overlying the getter layer, wherein the second memory cell comprises a second top electrode, a second bottom electrode, and a second data storage structure between the second top electrode and the second bottom electrode, wherein the second bottom electrode contacts the getter layer; and
wherein sidewalls of the first and second memory cells are respectively spaced laterally between sidewalls of the getter layer.
10. The memory device of claim 9 , wherein the getter layer comprises a single material that continuously laterally extends from the first memory cell to the second memory cell.
11. The memory device of claim 10 , wherein the single material is configured to absorb an outgas species.
12. The memory device of claim 7 , a bottom surface of the bottom electrode contacts a top surface of the getter layer.
13. The memory device of claim 7 , wherein a maximum width of the getter layer is greater than a maximum width of the first memory cell.
14. The memory device of claim 7 , further comprising:
a conductive wire overlying the first memory cell, wherein sidewalls of the conductive wire are spaced laterally between sidewalls of the getter layer.
15. A method for forming a memory device, the method comprising:
depositing a memory cell stack over a substrate, wherein the memory cell stack includes a bottom electrode, a getter layer abutting and underlying the bottom electrode, a data storage layer overlying the bottom electrode, and a top electrode overlying the data storage layer; and
performing a first patterning process on the memory cell stack to define a first memory cell such that sidewalls of the top electrode and sidewalls of the data storage layer are aligned.
16. The method of claim 15 , wherein sidewalls of the getter layer extend laterally past sidewalls of the first memory cell after performing the first patterning process.
17. The method of claim 16 , wherein the first patterning process does not etch through an entire thickness of the getter layer.
18. The method of claim 15 , wherein performing the first patterning process on the memory cell stack further defines a second memory cell over the getter layer, wherein the second memory cell is laterally offset from the first memory cell by a non-zero distance, and wherein the getter layer continuously laterally extends across the non-zero distance.
19. The memory cell of claim 1 , further comprising:
a dielectric layer underlying the getter layer; and
a conductive via disposed within the dielectric layer, wherein the conductive via contacts the getter layer.
20. The memory cell of claim 19 , wherein a lower surface of the getter layer is disposed along an upper surface of the dielectric layer.