Atomic layer deposition of hafnium or zirconium alloy films
Provided are methods of depositing hafnium or zirconium containing metal alloy films. Certain methods comprise sequentially exposing a substrate surface to alternating flows of an organometallic precursor and a reductant comprising M(BH 4 ) 4 to produce a metal alloy film on the substrate surface, wherein M is selected from hafnium and zirconium, and the organometallic precursor contains a metal N. Gate stacks are described comprising a copper barrier layer comprising boron, a first metal M selected from Hf and Zr, and a second metal N selected from tantalum, tungsten, copper, ruthenium, rhodium, cobalt and nickel; and a copper layer overlying the copper barrier seed layer.
1. A method of depositing a metal alloy film, the method comprising sequentially exposing a substrate surface to alternating flows of an organometallic precursor and a reductant comprising M(BH 4 ) 4 to produce a metal alloy film on the substrate surface, wherein M is selected from hafnium and zirconium, and the organometallic precursor contains a metal N selected from tantalum, tungsten, copper, ruthenium, rhodium, cobalt and nickel.
2. The method of claim 1 , wherein the metal alloy film comprises M, boron and the metal from the organometallic precursor.
3. The method of claim 2 , wherein the metal alloy film has a formula represented by M x B y N z .
4. The method of claim 1 , wherein the metal alloy film comprises M, boron and a metal selected from tantalum, tungsten, copper, ruthenium, rhodium, cobalt and nickel.
5. The method of claim 1 , wherein the film has a thickness of about 10-20 Å.
6. The method of claim 1 , wherein the substrate surface comprises a dielectric.
7. The method of claim 1 , wherein the substrate surface comprises TaN.
8. The method of claim 1 , further comprising depositing Ru on the metal alloy film.
9. The method of claim 1 , further comprising depositing Cu on the metal alloy film.
10. The method of claim 9 , wherein the deposited metal alloy film is a copper seed and barrier layer.
11. A method of depositing a metal alloy film, the method comprising:
a. sequentially exposing a substrate surface to alternating flows of an organometallic precursor and a reductant comprising Hf(BH 4 ) 4 to produce a metal alloy film on the substrate surface, and the organometallic precursor contains a metal N; and
b. subsequently forming a copper layer over the metal alloy film.
12. The method of claim 11 , wherein the film has a thickness of about 10-20 Å.