Materials and components in phase change memory devices
Phase change memory cells, structures, and devices having a phase change material and an electrode forming an ohmic contact therewith are disclosed and described. Such electrodes can have a resistivity of from 10 to 100 mOhm·cm.
1. A phase change memory cell, comprising:
a stack structure including:
a first electrode;
a second electrode; and
a phase change material disposed between and forming Ohmic contacts with the first electrode and the second electrode;
a third electrode; and
a select device material disposed between the third electrode and the second electrode;
wherein at least one of the first, second, or third electrodes includes an electrode material doped to have a resistivity of from about 10 to about 100 mOhm·cm;
wherein either:
at least the first and second electrodes include the doped electrode material;
at least the second and third electrodes include the doped electrode material; or
all of the first, second and third electrodes include the doped electrode material.
2. The memory cell of claim 1 , wherein at least the first and second electrodes include the doped electrode material.
3. The memory cell of claim 1 , wherein at least the second and third electrodes include the doped electrode material.
4. The memory cell of claim 1 , wherein all of the first, second, and third electrodes include the doped electrode material.
5. The memory cell of claim 1 , wherein the doped electrode material is amorphous carbon doped with silicon up to about 20 at %.
6. The memory cell of claim 1 , wherein the doped electrode material is tungsten silicide with an at % tungsten to silicon ratio of from about 1:3 to about 1:5 doped with nitrogen.
7. The memory cell of claim 1 , wherein the electrode material is a silicon carbide material with silicon being present in the silicon carbide material at a concentration of up to about 95 at % and the dopant is tungsten.
8. The memory cell of claim 7 , wherein the silicon carbide material has an at % silicon to carbon ratio of from about 1:1 to about 1:9.
9. The memory cell of claim 1 , wherein the doped electrode material has a resistivity of from about 10 to about 100 mOhm·cm when measured at a temperature of about 20° C.
10. The memory cell of claim 1 , wherein the doped electrode material has a resistivity of from about 10 to about 100 mOhm·cm following a 3 hour 400° C. anneal.
11. The memory cell of claim 1 , wherein the doped electrode material has a resistivity of from about 10 to about 100 mOhm·cm following at least 1000 write and erase cycles.
12. The memory cell of claim 1 , wherein the doped electrode material is a member selected from the group consisting of: amorphous carbon, tungsten silicide (WSi), and silicon carbide (SiC).
13. The memory cell of claim 1 , at least one of the electrodes is carbon and the dopant is silicon.
14. The memory cell of claim 1 , wherein two of the electrodes is carbon and the dopant is silicon.
15. The memory cell of claim 1 , wherein the first, second, and third electrodes are carbon and the dopant is silicon.
16. The memory cell of claim 1 , wherein the doped electrode material comprises silicon doped in amorphous carbon in an amount of from about 5 at % to about 10 at %.
17. The memory cell of claim 1 , wherein the doped electrode material comprises tungsten silicide and doped with nitrogen.
18. The memory cell of claim 17 , wherein the doped electrode material has an at % tungsten to silicon ratio of from about 1:3 to about 1:5.
19. The memory cell of claim 1 , wherein the doped electrode material is a silicon carbide material and the dopant is tungsten.
20. The memory cell of claim 19 , wherein the tungsten is doped in the silicon carbide material up to about 20 at %.
21. The memory cell of claim 1 , wherein the doped electrode material has a resistivity of from about 10 to about 100 mOhm·cm when measured at a temperature of from about 20° C. to about 400° C.
22. The memory cell of claim 1 , wherein the doped electrode material has a resistivity of from about 10 to about 100 mOhm·cm when measured at a temperature of about 20° C. and a temperature of about 600° C.
23. The memory cell of claim 1 , wherein the doped electrode material has a resistivity of from about 10 to about 100 mOhm·cm following manufacturing.
24. The memory cell of claim 1 , wherein the doped electrode material has a resistivity of from about 10 to about 100 mOhm·cm following a 3 hour 500° C. anneal.