Low-density, high-resistivity titanium nitride layer for use as a contact for low-leakage dielectric layers
A low-density, high-resistivity layer of a PVD sputter-deposited material, preferably titanium nitride, when coupled with a dielectric, makes a superior low-leakage insulating barrier for use in semiconductor devices. The material is created by sputtering methods that cause the ions to strike the deposition surface with reduced energy, for example in an ion metal plasma chamber with no self-bias accelerating ions normal to the deposition surface, or in a standard PVD chamber with pressure increased.
1. A semiconductor device comprising:
a first conductive or semiconductive layer;
a layer of titanium nitride, wherein at least a portion of the titanium nitride layer is more than about 20 angstroms thick, has resistivity greater than about 300 microOhm-cms and density less than 4.25 grams per cubic cm; and
a dielectric layer interposed between and in direct contact with the first conductive or semiconductive layer and the titanium nitride layer,
wherein the dielectric layer forms a dielectric rupture antifuse.
2. The semiconductor device of claim 1 wherein the titanium nitride layer is over the dielectric layer.
3. The semiconductor device of claim 2 wherein the first conductive or semiconductive layer comprises silicon.
4. The semiconductor device of claim 3 wherein the first conductive or semiconductive layer is silicon.
5. The semiconductor device of claim 4 wherein the first conductive or semiconductive layer is polysilicon.
6. The semiconductor device of claim 4 wherein the dielectric layer comprises silicon dioxide.
7. The semiconductor device of claim 6 wherein the silicon layer is a portion of a diode.
8. The semiconductor device of claim 1 wherein the dielectric layer is silicon nitride.
9. The semiconductor device of claim 8 wherein the device is a portion of a memory cell in a monolithic three dimensional memory.
10. The semiconductor device of claim 9 wherein the memory cells comprise pillars.
11. The semiconductor device of claim 9 wherein the memory cells are formed at the intersections of rails.
12. The semiconductor device of claim 1 wherein, for the portion of the titanium nitride layer more than about 20 angstroms thick, the density is less than about 4.0 grams per cubic cm.
13. A semiconductor device comprising:
a silicon layer;
in contact with the silicon layer, a layer of silicon dioxide or silicon nitride; and
in contact with the silicon dioxide or silicon nitride layer, a layer of nitrogen-rich titanium nitride, wherein at least a portion of the titanium nitride layer is more than about 20 angstroms thick, in that portion the ratio of titanium to nitrogen is greater than about 1.2:1, the density is less than 4.25 grams per cubic cm and resistivity is greater than about 300 microOhms-cms.
wherein the silicon dioxide or silicon nitride layer is interposed between the silicon layer and the titanium nitride layer,
wherein the layer of silicon dioxide or silicon nitride forms a dielectric rupture antifuse.
14. The device of claim 13 wherein the silicon dioxide or silicon nitride layer is over the silicon layer, and the titanium nitride is over the silicon dioxide or silicon nitride layer.
15. The device of claim 14 wherein the silicon layer comprises polysilicon.
16. The device of claim 15 wherein the device comprises a diode portion.
17. The device of claim 14 wherein the silicon dioxide or silicon nitride layer is thermally grown.
18. The device of claim 13 wherein at least a portion of the titanium nitride layer is more than about 20 angstroms thick, the portion is formed by physical vapor deposition with substantially no self-bias.
19. A monolithic three dimensional memory array comprising:
a polysilicon layer;
in contact with the polysilicon layer, a layer of silicon dioxide or
silicon nitride; and
in contact with the silicon dioxide or silicon nitride layer, a layer of titanium nitride, wherein at least a portion of the titanium nitride layer is more than about 20 angstroms thick, has resistivity greater than about 300 microOhm-cms and density less than 4.25 grams per cubic cm,
wherein the silicon dioxide or silicon nitride layer is interposed between the polysilicon layer and the titanium nitride layer, and
the layer of silicon dioxide or silicon nitride forms a dielectric rupture antifuse.
20. The monolithic three dimensional memory array of claim 19 , wherein the array comprises diode portions.
21. The monolithic three dimensional memory array of claim 20 , wherein the silicon dioxide or silicon nitride layer is silicon dioxide.
22. The monolithic three dimensional memory array of claim 20 , wherein the silicon dioxide or silicon nitride layer is silicon nitride.
23. A semiconductor device comprising:
a dielectric-rupture antifuse; and
a layer of low-density, high-resistivity titanium nitride in contact with the antifuse, and wherein at least a portion of the low-density, high-resistivity titanium nitride has a thickness greater than about 20 angstroms, and it is deposited by physical vapor deposition in a chamber with substantially no self-bias,
wherein the portion of the layer of low-density, high-resistivity titanium nitride has a resistivity greater than about 300 microOhm-cms and a density less than 4.25 grams per cubic cm.
24. The semiconductor device of claim 23 wherein the antifuse comprises silicon dioxide.
25. The semiconductor device of claim 23 wherein the antifuse comprises silicon nitride.
26. The semiconductor device of claim 23 wherein the titanium nitride is formed with a pressure in the chamber greater than about 15 mTorr.
27. The semiconductor device of claim 23 wherein the antifuse and the titanium nitride are portions of a monolithic three dimensional memory.
28. A semiconductor device comprising:
a first conductive or semiconductive layer;
a layer of titanium nitride wherein the resistivity of the titanium nitride is greater than about 300 microOhm-cms and the density is less than 4.25 grams per cubic cm; and
a dielectric layer interposed between and in direct contact with the first conductive or semiconductive layer and the titanium nitride layer,
wherein the the dielectric layer forms a dielectric rupture antifuse.
29. A semiconductor device comprising:
a silicon layer;
in contact with the silicon layer, a layer of silicon dioxide or silicon nitride; and
in contact with the silicon dioxide or silicon nitride layer, a layer of nitrogen-rich titanium nitride, wherein the ratio of titanium to nitrogen is greater than about 1.2:1 and the density is less 4.25 grams per cubic cm and resistivity is greater than about 300 microOhms-cms,
wherein the silicon dioxide or silicon nitride layer is interposed between the silicon layer and the titanium nitride layer,
wherein the layer of titanium nitride is deposited by physical vapor deposition in a chamber with substantially no self-bias; and the layer of silicon dioxide or silicon nitride forms a rupture antifuse.
30. A monolithic three dimensional memory array comprising:
a polysilicon layer;
in contact with the polysilicon layer, a layer of silicon dioxide or silicon nitride; and
in contact with the silicon dioxide or silicon nitride layer, a layer of titanium nitride, wherein the resistivity of the titanium nitride is greater than about 300 microQhm-cms and the density of the titanium nitride is less than 4.25 grams per cubic cm,
wherein the silicon dioxide or silicon nitride layer is interposed between the polysilicon layer and the titanium nitride layer, and
wherein the layer of silicon dioxide or silicon nitride forms a dielectric rupture antifuse.