Film stress control for memory device stack
Semiconductor structures are provided that include a memory device buried within interconnect dielectric materials and in which a combination of a compressive metal-containing layer and a tensile metal-containing layer have been used to minimize wafer bow and litho overlay shift as well as a method of forming such semiconductor structures.
1. A semiconductor structure comprising:
a bottom electrode located on a surface of a first electrically conductive structure, wherein the first electrically conductive structure is embedded in a first interconnect dielectric material layer;
a memory device pillar located on a surface of the bottom electrode, wherein the memory device pillar is a ferroelectric memory (FE) device pillar, a resistive random access memory (ReRAM) device pillar, a magnetoresistive random access memory (MRAM) device pillar, or a phase change random access memory (PRAM) device pillar; and
a top electrode located on the memory device pillar, wherein the top electrode includes a compressive metal-containing portion in direct physical contact with the memory device pillar, and a tensile metal-containing portion located directly on the compressive metal-containing portion.
2. The semiconductor structure of claim 1 , wherein the tensile metal-containing portion compensates the compressive stress caused by the compressive metal-containing portion.
3. The semiconductor structure of claim 1 , further comprising a second interconnect dielectric material layer located laterally adjacent to, and above, the memory device pillar and the top electrode, wherein a second electrically conductive structure is present in the second interconnect dielectric material layer and contacts a surface of the top electrode.
4. The semiconductor structure of claim 1 , wherein the bottom electrode is embedded in a dielectric capping layer.
5. The semiconductor structure of claim 1 , further comprising a passivation liner located on a sidewall of the memory device pillar and the top electrode.
6. The semiconductor structure of claim 1 , wherein the compressive metal-containing portion is composed of tantalum nitride, and the tensile metal-containing portion is composed of titanium nitride.
7. A semiconductor structure comprising:
a bottom electrode located on a surface of a first electrically conductive structure, wherein the first electrically conductive structure is embedded in a first interconnect dielectric material layer;
a first compressive metal-containing portion located above the bottom electrode;
a memory device pillar located on a surface of the first compressive metal-containing portion, wherein the memory device pillar is a ferroelectric memory (FE) device pillar, a resistive random access memory (ReRAM) device pillar, a magnetoresistive random access memory (MRAM) device pillar, or a phase change random access memory (PRAM) device pillar; and
a top electrode composed of a first tensile metal-containing portion located on the memory device pillar.
8. The semiconductor structure of claim 7 , further comprising a second tensile metal-containing portion located between the bottom electrode and the first compressive metal-containing portion, and a second compressive metal-containing portion located on a topmost surface of the first tensile metal-containing portion.
9. The semiconductor structure of claim 8 , wherein the first and second tensile metal-containing portions compensate the compressive stress caused by the first and second compressive metal-containing portions.
10. The semiconductor structure of claim 7 , further comprising a second interconnect dielectric material layer located laterally adjacent to, and above, the memory device pillar and the top electrode, wherein a second electrically conductive structure is present in the second interconnect dielectric material layer and contacts a surface of the top electrode.
11. The semiconductor structure of claim 7 , wherein the bottom electrode is embedded in a dielectric capping layer.
12. The semiconductor structure of claim 7 , further comprising a passsivation liner located on a sidewall of the memory device pillar and the top electrode.
13. A method of reducing wafer bowing in a semiconductor structure, the method comprising:
forming a bottom electrode located on a surface of a first electrically conductive structure, wherein the first electrically conductive structure is embedded in a first interconnect dielectric material layer;
forming a memory device stack above the bottom electrode and on a topmost surface of the first interconnect dielectric material layer, wherein a first compressive metal-containing layer contacts one surface of the memory device stack and the memory device stack is a ferroelectric memory (FE) device stack, a resistive random access memory (ReRAM) device stack, a magnetoresistive random access memory (MRAM) device stack, or a phase change random access memory (PRAM) device stack; and
forming a first tensile metal-containing layer above the memory device stack, wherein the first tensile metal-containing layer compensates the compressive stress caused by the first compressive metal-containing layer.
14. The method of claim 13 , wherein the one surface of the memory device stack is the bottommost surface, and the first tensile metal-containing layer directly contacts a topmost surface of the memory device stack.
15. The method of claim 13 , wherein the one surface of the memory device stack is the bottommost surface, and wherein a second tensile metal-containing layer is located between the first compressive metal-containing layer and the bottom electrode, and wherein the first tensile metal-containing layer is spaced apart from a topmost surface of the memory device stack by a second compressive metal-containing layer.
16. The method of claim 13 , wherein the one surface of the memory device stack is a topmost surface, and the first tensile metal-containing layer is located directly on a topmost surface of the first compressive metal-containing layer.
17. The method of claim 13 , further comprising:
patterning the memory device stack, the first compressive metal-containing layer, and the first tensile metal-containing layer to provide a patterned stack of the memory device stack, the first compressive metal-containing layer, and the first tensile metal-containing layer;
forming a passivation layer on physically exposed surfaces of the patterned stack; and
forming a second electrically conductive structure containing a topmost surface of patterned stack, wherein the second electrically conductive structure is embedded in a second interconnect dielectric material layer.