Silver-selenide/chalcogenide glass stack for resistance variable memory and manufacturing method thereof
View Patent ↗The invention is related to methods and apparatus for providing a resistance variable memory element with improved data retention and switching characteristics. According to an embodiment of the invention a resistance variable memory element is provided having at least one silver-selenide layer in between glass layers, wherein at least one of the glass layers is a chalcogenide glass, preferably having a Ge x Se 100-x composition.
1. A method of forming a resistance variable memory element, comprising:
forming a first glass material;
forming a silver-selenide material in contact with said first glass material, wherein said silver-selenide material comprises a plurality of silver-selenide layers in serial contact with each other; and
forming a second glass material in contact with said silver-selenide material, whereby one of said first and second glass materials comprises a chalcogenide glass material.
2. The method of claim 1 , wherein the forming of the first glass material comprises providing a plurality of first glass layers.
3. The method of claim 1 , wherein the first glass material comprises a chalcogenide glass.
4. The method of claim 3 , wherein the chalcogenide glass comprises Ge x Se 100-x , wherein x is between about 20 to 43.
5. The method of claim 1 , wherein the forming of the second glass material comprises providing a plurality of second glass layers.
6. The method of claim 1 , wherein the second glass material comprises a glass selected from the group consisting of silicon-selenide, arsenic-selenide, germanium-sulfide, and combinations of germanium, silver, and selenium.
7. The method of claim 6 , wherein the second glass material comprises up to about 3% of a dopant material.
8. The method of claim 1 , wherein the first glass material is formed to have a first thickness and the silver-selenide material is formed to have a second thickness greater than the first thickness.
9. The method of claim 8 , wherein the second glass material is formed to have a third thickness which is less than the second thickness.
10. The method of claim 9 , wherein the second thickness is up to 5 times greater than either one of the first thickness and the second thickness.
11. The method of claim 1 , further comprising:
providing a second silver-selenide material over the second glass material, wherein the second silver-selenide material comprises a plurality of second silver-selenide layers in serial contact with each other; and
providing a third glass material over the second silver-selenide material.
12. The method of claim 11 , wherein at least one of the first glass material, the second glass material, and the third glass material comprises a plurality of glass layers.
13. The method of claim 11 , further comprising:
providing a third silver-selenide material over the third glass material, wherein the third silver-selenide material comprises a plurality of third silver-selenide layers in serial contact with each other; and
providing a fourth glass material over the third silver-selenide material.
14. A resistance variable memory element comprising:
a first glass material;
a silver-selenide material in contact with said first glass material and comprising a plurality of silver-selenide layers in serial contact with each other; and
a second glass material in contact with said silver-selenide material, wherein one of said first and second glass materials comprises a chalcogenide glass material.
15. The resistance variable memory element of claim 14 , wherein the first glass material comprises a plurality of first glass layers.
16. The resistance variable memory element of claim 14 , wherein the first glass material comprises a chalcogenide glass.
17. The resistance variable memory element of claim 16 , wherein the chalcogenide glass comprises Ge x Se 100-x , wherein x is between about 20 to 43.
18. The resistance variable memory element of claim 14 , wherein the second glass material comprises a plurality of second glass layers.
19. The resistance variable memory element of claim 14 , wherein the second glass material comprises a glass selected from the group consisting of silicon-selenide, arsenic-selenide, germanium-sulfide, and combinations of germanium, silver, and selenium.
20. The resistance variable memory element of claim 19 , wherein the second glass material comprises up to about 3% of a dopant material.
21. The resistance variable memory element of claim 14 , wherein the first glass material has a first thickness and the silver-selenide material has a second thickness greater than the first thickness.
22. The resistance variable memory element of claim 21 , wherein the second glass material has a third thickness which is less than the second thickness.
23. The resistance variable memory element of claim 22 , wherein the second thickness is up to 5 times greater than either one of the first thickness and the second thickness.
24. The resistance variable memory element of claim 14 , further comprising:
a second silver-selenide material over the second glass material, wherein the second silver-selenide material comprises a plurality of second silver-selenide layers in serial contact with each other; and
a third glass material over the second silver-selenide material.
25. The resistance variable memory element of claim 24 , wherein at least one of the first glass material, the second glass material, and the third glass material comprises a plurality of glass layers.
26. The resistance variable memory element of claim 24 , further comprising:
a third silver-selenide material over the third glass material, wherein the third silver-selenide material comprises a plurality of third silver-selenide layers in serial contact with each other; and
a fourth glass material over the third silver-selenide material.