Method of aligning deposited nanotubes onto an etched feature using a spacer
View Patent ↗A method of forming an aligned connection between a nanotube layer and a raised feature is disclosed. A substrate having a raised feature has spacers formed next to the side of the raised feature. The spacers are etched until the sidewalls of the raised feature are exposed forming a notched feature at the top of the spacers. A patterned nanotube layer is formed such that the nanotube layer overlies the top of the spacer and contacts a side portion of the raised feature in the notched feature. The nanotube layer is then covered with an insulating layer. Then a top portion of the insulating layer is removed to expose a top portion of the etched feature.
1. A carbon nanotube electrical connection to a raised feature, the connection comprising:
a raised feature formed on a substrate, the raised feature having a top portion, and a sidewall;
a sidewall spacer formed next to the sidewall of the raised feature and exposing a portion of the sidewall near the top of the raised feature, thereby defining a notched region above the spacer;
a nanotube layer formed on the substrate such that the nanotube layer contacts an exposed portion of the sidewall and overlies the spacer in the notched region; and
an insulating layer on the substrate that covers the nanotube layer and leaves a portion of the top of the raised feature exposed.
2. The carbon nanotube electrical connection of claim 1 , wherein the raised feature comprises a raised metallization layer.
3. The carbon nanotube electrical connection of claim 1 , wherein the raised feature comprises a transistor gate stack.
4. The carbon nanotube electrical connection of claim 1 , wherein the raised feature comprises a metal-containing material.
5. The carbon nanotube electrical connection of claim 4 , wherein the metal-containing material comprises a material selected from among aluminum, tungsten, tantalum, and titanium.
6. The carbon nanotube electrical connection of claim 4 , wherein the metal-containing material comprise a metal alloy.
7. The carbon nanotube electrical connection of claim 4 , wherein the metal-containing material comprises a metal nitride.
8. The carbon nanotube electrical connection of claim 1 , wherein the raised feature comprises more than one layer of metal-containing material.
9. The carbon nanotube electrical connection of claim 1 , wherein the notched region extends downward exposing no more than half of the height of the side of the raised feature.
10. The carbon nanotube electrical connection of claim 1 , wherein the raised feature is formed using chemical mechanical polishing.
11. The carbon nanotube electrical connection of claim 1 , the raised feature is formed using etching.
12. The carbon nanotube electrical connection of claim 1 , wherein the insulating layer comprises silicon dioxide.