Trench-based capacitor for integrated circuits
View Patent ↗In one embodiment, an electrically conductive trench in an integrated circuit allows for the formation of capacitors between the trench and other portions of the integrated circuit. For example, a capacitor may be formed between the trench and an electrically conductive line. Among other advantages, the capacitor provides a relatively large capacitance while occupying a relatively small area.
1. An integrated circuit structure comprising:
a plurality of electrically conductive lines over a substrate;
a plurality of electrically conductive trenches over the plurality of electrically conductive lines, each of the plurality of electrically conductive trenches spanning and filling a space between at least two electrically conductive lines in the plurality of electrically conductive lines; and
a capacitor designed for use as a component of an electrical circuit, the capacitor formed using at least a first electrically conductive trench in the plurality of electrically conductive trenches.
2. The integrated circuit structure of claim 1 wherein the capacitor is formed by the first electrically conductive trench, a sidewall of a first electrically conductive line in the plurality of electrically conductive lines, and a dielectric between the first electrically conductive trench and the sidewall of the first electrically conductive line.
3. The integrated circuit structure of claim 1 wherein the capacitor is formed by the first electrically conductive trench, a top portion of a first electrically conductive line in the plurality of electrically conductive lines, and a dielectric between the first electrically conductive trench and the top portion of the first electrically conductive line.
4. The integrated circuit structure of claim 1 wherein the capacitor is formed by the first electrically conductive trench, a second electrically conductive trench in the plurality of electrically conductive trenches, and a dielectric between the first electrically conductive trench and the second electrically conductive trench.
5. The integrated circuit structure of claim 1 wherein the plurality of electrically conductive trenches is across the plurality of electrically conductive lines.
6. The integrated circuit structure of claim 1 wherein the electrically conductive trenches comprise tungsten.
7. The integrated circuit structure of claim 1 further comprising spacers formed on sidewalls of the electrically conductive lines.
8. The integrated circuit structure of claim 1 further comprising:
a plurality of local interconnect lines formed over and across the plurality of electrically conductive trenches.
9. The integrated circuit structure of claim 8 wherein the capacitor is formed by a first local interconnect line in the plurality of local interconnect lines, the first electrically conductive trench, and a dielectric between the first local interconnect line and the first electrically conductive trench.
10. The integrated circuit structure of claim 8 further comprising a plurality of first level interconnect lines formed over and across the plurality of local interconnect lines.