Composite chalcogenide materials and devices
View Patent ↗An electrical device includes a composite switching material. The composite switching material includes an electrically switchable component and a non-switchable component. In one embodiment, the composite switching material includes a heterogeneous mixture of at least one chalcogenide material and at least one dielectric material. The composite switching material is disposed between two electrodes and the switchable component is transformable from a resistive state to a conductive state upon application of a voltage between the two electrodes, without changing phase.
1. An electrical device comprising:
a first electrode;
an insulating layer surrounding said first electrode;
a second electrode; and
a composite switching material disposed between said first electrode and said second electrode, said composite switching material including a switchable component and a non-switchable component, said switchable component having a resistive state and a conductive state, said switchable component switching from said resistive state to said conductive state upon application of a voltage between said first electrode and said second electrode.
2. The electrical device of claim 1 , wherein said switchable component and said non-switchable component form a heterogeneous layer between said first electrode and said second electrode.
3. The electrical device of claim 1 , wherein the volume fraction of said non-switchable component in said composite switching material is between 5 percent and 90 percent.
4. The electrical device of claim 1 , wherein the volume fraction of said non-switchable component in said composite switching material is between 5 percent and 20 percent.
5. The electrical device of claim 1 , wherein said switchable component comprises a chalcogenide material.
6. The electrical device of claim 5 , wherein said chalcogenide material comprises Te or Se.
7. The electrical device of claim 6 , wherein said chalcogenide material further comprises Ge and As.
8. The electrical device of claim 1 , wherein said non-switchable component comprises a dielectric material.
9. The electrical device of claim 8 , wherein said dielectric comprises a material selected from the group consisting of oxides, nitrides, carbides, oxynitrides, and borides.
10. The electrical device of claim 9 , wherein said dielectric material comprises silicon.
11. The electrical device of claim 1 , wherein said switchable component is in said resistive state when the voltage applied across said first electrode and said second electrode is less than a first voltage.
12. The electrical device of claim 11 , wherein said switchable component switches to said conductive state when the voltage applied across said first electrode and said second electrode is equal to or greater than said first voltage, said device conducting at least a first current between said first electrode and said second electrode in said conductive state.
13. The electrical device of claim 12 , wherein said switchable component returns to said resistive state when the current passing between said first electrode and said second electrode is less than said first current.
14. The electrical device of claim 1 , wherein said conductive state of said switchable component comprises a conductive filament, said conductive filament extending from said first electrode to said second electrode.
15. The electrical device of claim 14 , wherein said conductive state of said switchable component comprises a first region and a second region, said first region comprising said conductive filament, said second region comprising said switchable component in said resistive state.
16. The electrical device of claim 1 , wherein said insulating layer includes a hole, said first electrode occupying said hole.
17. The electrical device of claim 1 , wherein said first electrode contacts said composite switching material.
18. The electrical device of claim 17 , wherein said second electrode contacts said composite switching material.
19. The electrical device of claim 18 , wherein the area of contact of said first electrode with said composite switching material is less than the area of contact of said second electrode with said composite switching material.
20. The electrical device of claim 2 further comprising
a second layer, said second layer disposed between said heterogeneous composite switching layer and said first electrode.
21. The electrical device of claim 20 , wherein said second layer comprises a chalcogenide material.
22. The electrical device of claim 21 , wherein said second layer further comprises a dielectric material dispersed within said chalcogenide material.
23. The electrical device of claim 21 , wherein said chalcogenide material is a switchable chalcogenide material.