Methods of forming and using fuses
View Patent ↗Some embodiments include a fuse having a tungsten-containing structure directly contacting an electrically conductive structure. The electrically conductive structure may be a titanium-containing structure. An interface between the tungsten-containing structure and the electrically conductive structure is configured to rupture when current through the interface exceeds a predetermined level. Some embodiments include a method of forming and using a fuse. The fuse is formed to have a tungsten-containing structure directly contacting an electrically conductive structure. An interface between the tungsten-containing structure and the electrically conductive structure is configured to rupture when current through the interface exceeds a predetermined level. Current exceeding the predetermined level is passed through the interface to rupture the interface.
1. A method of using a fuse, comprising:
providing the fuse to comprise a tungsten-containing structure directly contacting a titanium-containing structure; the tungsten containing structure having a circular uppermost surface with a total area and contacting the titanium-containing structure only at an interface between the uppermost surface of the tungsten-containing and the titanium-containing structure, the interface being circular and having a total area of less than or equal to 1500 nm 2 , the interface having an area that is less than the total area of the uppermost surface, the interface being configured to rupture when current through said interface exceeds a predetermined level;
passing current exceeding the predetermined level through the interface to rupture the interface;
wherein the fuse is formed adjacent a PCRAM array;
wherein at least one of the tungsten-containing structure and the titanium-containing structure is identical in composition with a structure of the PCRAM array; and
wherein the titanium-containing structure comprises titanium nitride doped with one or more of aluminum, silicon and carbon.
2. The method of claim 1 wherein at least one of the tungsten-containing structure and the titanium-containing structure is formed simultaneously with a structure of the PCRAM array.
3. The method of claim 2 wherein the tungsten-containing structure is formed simultaneously with a tungsten-containing structure of the PCRAM array.
4. The method of claim 2 wherein the titanium-containing structure is formed simultaneously with titanium-containing heater structures of PCRAM cells of the PCRAM array.
5. The method of claim 1 further comprising, after rupturing the interface, resetting the fuse by flowing current across the ruptured interface.
6. The method of claim 5 wherein the resetting comprises flowing current of an opposite polarity as compared to current utilized to rupture the interface.
7. The method of claim 1 wherein the rupture utilizes electron wind.
8. The method of claim 1 wherein the tungsten-containing structure consists of tungsten.