Barrier layer for integrated circuit contacts
View Patent ↗Plug contacts may be formed with barrier layers having thicknesses of less than 50 Å in some embodiments. In one embodiment, the barrier layer may be formed by the chemical vapor deposition of diborane, forming a boron layer between a metallic contact and the surrounding dielectric and between a metallic contact and the substrate and/or substrate contact. This boron layer may be substantially pure boron and boron silicide.
1. A method comprising:
forming a contact aperture in a dielectric material that is formed over a substrate, the substrate including a contact formed therein;
forming a barrier layer including boron and having a thickness of less than 50 Angstroms between a metal fill and the contact aperture, a layer including titanium formed over the contact and wherein the barrier layer is formed over the layer including titanium.
2. The method of claim 1 including forming said barrier layer by the chemical vapor deposition of diborane.
3. The method of claim 1 including forming the barrier layer substantially only boron.
4. The method of claim 1 including forming said barrier layer of boron silicide.
5. The method of claim 1 including forming the barrier layer between the dielectric material and the metal fill.
6. The method of claim 1 including extending said barrier layer from the contact to a wall of said contact aperture.
7. The method of claim 1 including keeping the region between walls of the contact aperture and the metal fill free of titanium nitride.
8. The method of claim 1 , further comprising forming the contact in the substrate from titanium silicide.
9. The method of claim 1 , further comprising forming the metal fill from tungsten.