Selective metal deposition over dielectric layers
Selective deposition of metal over dielectric layers in a manner that minimizes of eliminates keyhole formation is provided. According to one embodiment, a dielectric target layer is formed over a substrate layer, wherein the target layer may be configured as allow conformal metal deposition, and a dielectric second layer is formed over the target layer, wherein the second layer may be configured to allow bottom-up metal deposition. An opening may then be formed in the second layer and metal may be selectively deposited over substrate layer.
1. A method of performing selective electroless plating comprising:
providing a substrate having a first dielectric layer thereover, the first dielectric layer having a non-catalytic surface;
forming a conductive layer directly on a portion of the first dielectric layer;
forming a hydrogen rich target layer over the conductive layer:
forming a second dielectric layer over the target layer;
forming an opening to form a contact on the conductive layer;
performing selective electroless plating of a thin film over the contact.
2. The method of claim 1 wherein the target layer is hydrogen rich dielectric.
3. The method of claim 1 wherein the target layer is chlorine rich dielectric.
4. The method of claim 1 wherein the second dielectric layer is oxide based.
5. The method of claim 1 wherein the second dielectric layer is hydrogen poor relative to the target layer.
6. The method of claim 1 further comprising performing a preclean prior to performing selective electroless plating.
7. The method of claim 1 wherein the thin film comprises one or more members of the group consisting of nickel, thallium, phosphorous, gold, silver, copper, cobalt, palladium, platinum, boron, rhodium, iron, tungsten, binary alloys of these metals and ternary alloys of these metals.
8. The method of claim 1 wherein the thin film comprises a ternary alloy of nickel, thallium and boron.
9. The method of claim 1 wherein the thin film comprises a ternary ally of nickel, phosphorous and copper.