Granted Patent B2

US 8,883,639 · App. 13/358,137 · Granted Nov 11, 2014

Abstract

Claims (31)

1. A method of forming a semiconductor device over a substrate, comprising:

forming a first conductive layer over the substrate;

forming a first dielectric layer over the first conductive layer;

forming a first opening in the first dielectric layer;

depositing a seed layer over the first dielectric layer and in the first opening;

forming a layer of conductive nanotubes from the seed layer over the first dielectric layer and over the first opening;

forming a second dielectric over the layer of conductive nanotubes;

forming a second opening in the second dielectric layer over the first opening; and

depositing conductive material in the second opening,

wherein a first portion of the conductive nanotubes extends from the first dielectric layer to the second dielectric layer and a second portion of the conductive nanotubes extends from the first conductive layer to the conductive material.

2. The method of claim 1 , wherein the step of forming the first conductive layer comprises:

forming a copper layer; and

forming a titanium/tantalum layer on the copper layer.

3. The method of claim 1 , wherein the step of depositing the seed layer comprises forming a cobalt layer.

4. The method of claim 3 , wherein the step of depositing the seed layer is further characterized by the cobalt layer comprising discrete seeds of cobalt that are spaced apart.

5. The method of claim 1 , wherein step of forming the layer of conductive nanotubes is further characterized by the conductive nanotubes comprising carbon nanotubes.

6. The method of claim 5 , wherein the step of forming the layer of nanotubes is further characterized by the layer of nanotubes being homogeneous.

7. The method of claim 1 , wherein the step of depositing conductive material comprises depositing copper.

8. The method of 7 , wherein the step of depositing conductive material further comprises depositing a barrier metal prior to depositing the copper.

9. The method of claim 1 , further comprising performing an anneal to cause the seed layer to form an alloy with the conductive layer.

10. The method of claim 9 , wherein the step of annealing causes the seed layer on the first dielectric layer to be absorbed by the first dielectric layer.

11. The method of claim 1 , wherein the first portion functions as a conductive via and the second portion functions as an interlayer dielectric surrounding the conductive via further comprising forming an insulating layer over the conductive nanotubes, wherein the insulating layer has an opening and the metal contact is in the opening.

12. A method of forming a via, comprising:

forming a conductive line over a substrate;

forming an insulating layer over the conductive line;

forming an opening in the insulating layer to expose a portion of the conductive line;

forming a discrete seeds that are apart, a first plurality of the discrete seeds being on the portion of the conductive line that is exposed, a second plurality of the discrete seeds being on the insulating layer;

simultaneously growing conductive nanotubes on the first plurality of discrete seeds and on the second plurality of discrete seeds; and

forming a metal contact to the conductive nanotubes grown from the first plurality of seeds, whereby the conductive nanotubes that are grown from the first plurality of seeds and that are in contact with the metal contact function as the via, the via electrically connecting the metal contact to the conductive line,

the method further comprising:

forming an insulating layer over the conductive nanotubes, wherein the insulating layer has an opening and the metal contact is in the opening, and wherein the conductive nanotubes grown from the second plurality of seeds function as an interlayer dielectric surrounding the via.

Assignments (22)