Molecular self-assembly in substrate processing
Systems and methods for molecular self-assembly are provided. The molecular self-assembly receives a substrate that includes one or more regions of dielectric material. A molecularly self-assembled layer is formed on an exposed surface of the dielectric material. The molecularly self-assembled layer includes material(s) having a molecular characteristic and/or a molecular type that includes one or more of a molecular characteristic and/or a molecular type of a head group of molecules of the material, a molecular characteristic and/or a molecular type of a terminal group of molecules of the material, and a molecular characteristic and/or a molecular type of a linking group of molecules of the material. The molecular characteristic(s) and molecular type(s) are selected according to at least one pre-specified property of the molecularly self-assembled layer.
1. A method of using a self assembled monolayer (SAM) on a substrate with vias, the substrate containing exposed dielectric surfaces and recessed conductive surfaces within the vias, comprising:
selectively forming the SAM on the dielectric surfaces;
cleaning contaminants from the conductive surfaces; and
removing the SAM from the dielectric surfaces along with any contaminants captured by the SAM during the cleaning.
2. The method of claim 1 , wherein the SAM protects the dielectric surfaces during the cleaning and collects any contaminants re-deposited during the cleaning.
3. The method of claim 1 , wherein forming of the SAM comprises forming the SAM to include a terminal group to enhance subsequent processing of the substrate.
4. The method of claim 1 , wherein the SAM is conformal.
5. The method of claim 1 , comprising cleaning the dielectric surfaces prior to forming the SAM.
6. The method of claim 1 , wherein the cleaning and the removing are included in a single etch process.
7. The method of claim 1 , wherein the cleaning is a wet process.
8. The method of claim 7 , wherein the wet process uses a solution selected from a group consisting of low pH cleaning, high pH cleaning, reducing and etching solutions.
9. The method of claim 1 , wherein the vias are formed using a Damascene process or a dual-Damascene process.
10. The method of claim 9 , comprising processing the substrate following removing of the SAM, the processing selected from a group consisting of depositing a barrier layer, depositing a seed layer, and bulk copper filling.
11. The method of claim 1 , comprising forming anchors in the conductive surfaces by removing a portion of conductive material from the conductive surfaces during the cleaning.
12. The method of claim 11 , wherein a depth of the anchors is approximately in a range of 50 to 400 angstroms.
13. The method of claim 11 , comprising forming a capping layer on the conductive surfaces before removing the SAM.
14. The method of claim 13 , where the capping layer is formed of a metal or metal alloy.
15. The method of claim 14 , wherein the capping layer is formed through electroless deposition.
16. The method of claim 13 , wherein the SAM has a terminal group that impedes formation of the capping layer.
17. The method of claim 13 , wherein removing the SAM includes removing any capping layer material deposited on the SAM.
18. A method of processing a substrate having exposed dielectric surfaces and recessed conductive surfaces in a via, comprising:
forming a self assembled monolayer (SAM) on the dielectric surfaces of the substrate;
removing contaminants from the conductive surfaces, wherein the SAM binds contaminants re-deposited during contaminant removal; and
removing the SAM, wherein the contaminants bound to the SAM are removed.
19. The method of claim 18 , comprising forming a capping layer on the conductive surfaces following the removing of the contaminants from the conductive surfaces.
20. The method of claim 19 , wherein the forming of the capping layer includes electroless plating.
21. A method of processing a substrate having exposed dielectric surfaces and recessed conductive surfaces in a via, comprising:
forming a self assembled monolayer (SAM) on the dielectric surfaces of the substrate;
cleaning contaminants from the conductive surfaces and forming a capping layer on the conductive surfaces; and
removing the SAM, wherein removing the SAM includes removing any contaminants re-deposited during the cleaning and any capping layer material deposited on the SAM.