Modifying ferroelectric properties of hafnium oxide with hafnium nitride layers

1. A method of forming ferroelectric hafnium oxide (HfO 2 ) of a ferroelectric random access memory (FeRAM) memory structure, in a substrate processing system, the method comprising:

depositing a first HfO 2 layer on a substrate;

depositing a hafnium nitride (HfN) layer on the first HfO 2 layer;

depositing a second HfO 2 layer on the HfN layer, the second HfO 2 layer having the same material as the first HfO 2 layer;

depositing a top electrode on the second HfO 2 layer; and

annealing the first HfO 2 layer, the second HfO 2 layer, the HfN layer, and the top electrode to form ferroelectric hafnium HfO 2 of the FeRAM memory structure,

wherein annealing the first HfO 2 layer, the second HfO 2 layer, the HfN layer, and the top electrode includes performing a rapid thermal annealing process at a temperature between 750 and 1100° C.

2. The method of claim 1 , further comprising performing oxidation on the HfN layer.

3. The method of claim 2 , wherein performing the oxidation on the HfN layer includes performing the oxidation using at least one of molecular oxygen and ozone.

4. The method of claim 1 , further comprising nitridating the first HfO 2 layer prior to depositing the HfN layer.

5. The method of claim 4 , wherein nitridating the first HfO 2 layer includes generating plasma using a nitrogen gas species.

6. The method of claim 1 , wherein the top electrode comprises a material selected from a group consisting of titanium, tantalum, and tungsten.

7. The method of claim 1 , further comprising depositing a bottom electrode on the substrate and depositing the first HfO 2 layer on the bottom electrode.

8. The method of claim 1 , wherein the first HfO 2 layer is doped using a dopant species selected from a group consisting of silicon (Si), aluminum (Al), yttrium (Y), zirconium (Zr), and/or lanthanum (La).

9. A system configured to form ferroelectric hafnium oxide (HfO 2 ) on a substrate of a ferroelectric random access memory (Fe RAM) memory structure, in a processing chamber, the system comprising:

a gas delivery system configured to supply gases to the processing chamber;

a radio frequency (RF) generating system configured to generate plasma within the processing chamber; and

a controller configured to, by controlling the gas delivery system and the RF generating system,

deposit a first HfO 2 layer on the substrate,

deposit a hafnium nitride (HfN) layer on the first HfO 2 layer,

deposit a second HfO 2 layer on the HfN layer, the second HfO 2 layer having the same material as the first HfO 2 layer,

deposit a top electrode on the second HfO 2 layer; and

anneal the first HfO 2 layer, the second HfO 2 layer, the HfN layer, and the top electrode to form ferroelectric hafnium HfO 2 of the Fe RAM memory structure,

wherein annealing the first HfO 2 layer, the second HfO 2 layer, the HfN layer, and the top electrode to form ferroelectric hafnium HfO 2 includes performing a rapid thermal annealing process at a temperature between 750 and 1100° C.

10. The system of claim 9 , wherein the controller is further configured to perform oxidation on the HfN layer.

11. The system of claim 10 , wherein performing the oxidation on the HfN layer includes performing the oxidation using at least one of molecular oxygen and ozone.

12. The system of claim 9 , wherein the controller is further configured to nitridate the first HfO 2 layer prior to depositing the HfN layer.

13. The system of claim 12 , wherein nitridating the first HfO 2 layer includes generating plasma using a nitrogen gas species.

14. The system of claim 9 , wherein the top electrode comprises a material selected from a group consisting of titanium, tantalum, and tungsten.

15. The system of claim 9 , wherein the controller is further configured to deposit a bottom electrode on the substrate and deposit the first HfO 2 layer on the bottom electrode.

16. The system of claim 9 , wherein the first HfO 2 layer is doped using a dopant species selected from a group consisting of silicon (Si), aluminum (Al), yttrium (Y), zirconium (Zr), and/or lanthanum (La).