Methods of forming a ferroelectric memory cell
View Patent ↗A method of forming a ferroelectric memory cell. The method comprises forming an electrode material exhibiting a desired dominant crystallographic orientation. A hafnium-based material is formed over the electrode material and the hafnium-based material is crystallized to induce formation of a ferroelectric material having a desired crystallographic orientation. Additional methods are also described, as are semiconductor device structures including the ferroelectric material.
1. A method of forming a ferroelectric memory cell, comprising:
forming a titanium nitride material in a dominant (111) crystallographic orientation;
forming a hafnium-based material over the titanium nitride material; and
crystallizing the hafnium-based material to induce formation of a dominant (200) crystallographic orientation of the hafnium-based material.
2. The method of claim 1 , wherein forming a hafnium-based material over the titanium nitride material comprises forming a hafnium oxide material over the titanium nitride material.
3. The method of claim 1 , wherein forming a hafnium-based material over the titanium nitride material comprises forming an amorphous hafnium-based material over the titanium nitride material.
4. The method of claim 1 , wherein forming a hafnium-based material over the titanium nitride material comprises forming a hafnium-based material lacking ferroelectric properties over the titanium nitride material.
5. The method of claim 1 , wherein forming a hafnium-based material over the titanium nitride material comprises forming the hafnium-based material by sputtering.
6. The method of claim 1 , wherein forming a hafnium-based material over the titanium nitride material comprises forming the hafnium-based material by chemical vapor deposition.
7. The method of claim 1 , wherein forming a hafnium-based material over the titanium nitride material comprises forming the hafnium-based material by plasma-enhanced chemical vapor deposition.
8. The method of claim 1 , wherein forming a hafnium-based material over the titanium nitride material comprises forming the hafnium-based material by atomic layer deposition.
9. The method of claim 1 , wherein forming a hafnium-based material over the titanium nitride material comprises forming hafnium silicate, hafnium aluminate, hafnium zirconate, strontium-doped hafnium oxide, magnesium-doped hafnium oxide, gadolinium-doped hafnium oxide, yttrium-doped hafnium oxide, or combinations thereof over the titanium nitride material.
10. The method of claim 1 , wherein crystallizing the hafnium-based material comprises annealing the hafnium-based material at a temperature of from about 800° C. to about 1000° C.
11. The method of claim 1 , further comprising forming an electrode material over the dominant (200) crystallographic orientation of the hafnium-based material.
12. The method of claim 11 , wherein forming an electrode material over the dominant (200) crystallographic orientation of the hafnium-based material comprises forming the electrode material over the dominant (200) crystallographic orientation of the hafnium-based material before crystallizing the hafnium-based material.
13. A method of forming a ferroelectric memory cell, comprising:
forming a titanium nitride material in a dominant (111) crystallographic orientation;
forming a hafnium oxide material over the titanium nitride material, the hafnium oxide material lacking ferroelectric properties; and
crystallizing the hafnium oxide material to form a crystallized hafnium oxide material having ferroelectric properties and a dominant (200) crystallographic orientation.
14. The method of claim 13 , wherein forming a hafnium oxide material over the titanium nitride material comprises forming a magnesium-doped hafnium oxide over the titanium nitride material.
15. The method of claim 13 , further comprising forming another titanium nitride material over the hafnium oxide material.
16. The method of claim 15 , wherein forming another titanium nitride material over the hafnium oxide material comprises forming a crystalline titanium nitride material over the hafnium oxide material.
17. The method of claim 15 , wherein forming another titanium nitride material over the hafnium oxide material comprises forming titanium nitride in a (001), (002), (100), (110), (111), or (200) crystallographic orientation over the hafnium oxide material.
18. The method of claim 15 , wherein forming another titanium nitride material over the hafnium oxide material comprises forming the another titanium nitride material comprising a different crystallographic orientation than the titanium nitride material.
19. The method of claim 15 , wherein forming another titanium nitride material over the hafnium oxide material comprises forming the another titanium nitride material comprising the same crystallographic orientation as the titanium nitride material.
20. The method of claim 15 , wherein forming another titanium nitride material over the hafnium oxide material comprises forming the another titanium nitride material over the hafnium oxide material before crystallizing the hafnium oxide material.
21. The method of claim 15 , further comprising forming a metal silicide material over the another titanium nitride material.
22. The method of claim 13 , wherein forming a hafnium oxide material over the titanium nitride material and crystallizing the hafnium oxide material comprises forming hafnium silicate over the titanium nitride material and crystallizing the hafnium silicate to form orthorhombic hafnium silicate.
23. The method of claim 13 , wherein forming a hafnium oxide material over the titanium nitride material and crystallizing the hafnium oxide material comprises forming hafnium silicate over the titanium nitride material and crystallizing the hafnium silicate to form orthorhombic hafnium silicate in the dominant (200) crystallographic orientation.