ALD of metal-containing films using cyclopentadienyl compounds

1. An atomic layer deposition (ALD) process for producing metal containing thin films comprising alternately and sequentially contacting a substrate in a reaction space with vapor phase pulses of at least one volatile metal containing cyclopentadienyl compound and a second reactant at a temperature that is low enough to prevent decomposition of the cyclopentadienyl compound and the second reactant, wherein the metal containing cyclopentadienyl compound comprises a metal with a trivalent oxidation state, wherein said cyclopentadienyl compound does not contain a metal directly bonded to a halide or oxygen atom, and wherein the metal containing cyclopentadienyl compound has the formula: (R 1 R 2 R 3 R 4 R 5 Cp) x -MR 0 z —(NR 1 R 2 ) y

wherein M is titanium;

wherein each R 1 , R 2 , R 3 , R 4 , R 5 , and R 0 is independently selected from:

(i) hydrogen;

(ii) linear and branched C 1 -C 20 alkyl, alkenyl and alkynyl groups, which are independently substituted or unsubstituted;

(iii) carbocyclic groups, such as aryl, phenyl, cyclopentadienyl, alkylaryl, and halogenated carbocyclic groups; and

(iv) heterocyclic groups; and

wherein both x and y are ≧1 and z≧0.

2. The process according to claim 1 , wherein the metal containing cyclopentadienyl compound does not comprise halide or oxygen atoms.

3. The process according to claim 1 , wherein the metal containing cyclopentadienyl compound comprises at least one ligand that is bonded to the metal via nitrogen.

4. The process according to claim 1 , wherein the metal containing cyclopentadienyl compound comprises a modified cyclopentadienyl group.

5. The process according claim 4 , wherein the metal containing cyclopentadienyl compound comprises a modified cyclopentadienyl group selected from the group consisting of Me 5 Cp, MeCp, EtCp, and Me 3 SiCp.

6. The process according to claim 1 , wherein the second reactive precursor is a nitrogen containing compound.

7. The process according to claim 6 , wherein the nitrogen containing compound is selected from a group consisting of NH 3 , N 2 plasma, N 2 /H 2 plasma, hydrazine, and/or hydrazine derivatives.

8. An atomic layer deposition (ALD) process for producing metal containing thin films comprising alternately and sequentially contacting a substrate in a reaction space with vapor phase pulses of at least one metal containing cyclopentadienyl compound and a second reactant, wherein said cyclopentadienyl compound does not contain a metal directly bonded to a halide or oxygen atom, wherein the metal containing cyclopentadienyl compound has the formula(R 1 R 2 R 3 R 4 R 5 Cp) x MR 0 z —[(NR 1 R 2 )CNR 3 ] y

wherein M is titanium;

wherein each R 1 , R 2 , R 3 , R 4 , R 5 , and R 0 is independently selected from:

(i) hydrogen;

(ii) linear and branched C 1 -C 20 alkyl, alkenyl and alkynyl groups, which are independently substituted or unsubstituted;

(iii) carbocyclic groups, such as aryl, phenyl, cyclopentadienyl, alkylaryl, and halogenated carbocyclic groups; and

(iv) heterocyclic groups; and

wherein both x and y are ≧1 and z≧0.

9. The process according to claim 8 , wherein the metal containing cyclopentadienyl compound is biscyclopentadienyl triisopropylguanidinato titanium (III).

10. The process according to claim 8 , wherein the metal containing cyclopentadienyl compound further comprises a dianionic guanidinate ligand.

11. An atomic layer deposition (ALD) process for producing metal containing thin films comprising alternately and sequentially contacting a substrate in a reaction space with vapor phase pulses of at least one metal containing cyclopentadienyl compound and a second reactant, wherein said cyclopentadienyl compound does not contain a metal directly bonded to a halide or oxygen atom, wherein the metal containing cyclopentadienyl compound is depicted by the formula: (R 1 R 2 R 3 R 4 R 5 Cp) x MR 0 z —[(NR 1 NR 2 )CNR 3 R 4 ] y

wherein M is titanium;

wherein each R 1 , R 2 , R 3 , R 4 , R 5 , and R 0 is independently selected from:

hydrogen;

(ii) linear and branched C 1 -C 20 alkyl, alkenyl and alkynyl groups, which are independently substituted or unsubstituted;

(iii) carbocyclic groups, such as aryl, phenyl, cyclopentadienyl, alkylaryl, and halogenated carbocyclic groups; and

(iv) heterocyclic groups; and

wherein both x and y are ≧1 and z≧0.

12. An ALD process for producing a metal thin film comprising:

feeding a vapor phase pulse of a first reactant into the reaction chamber, wherein the first reactant is a biscyclopentadienyl triisopropylguanidinato titanium compound;

removing the first reactant from the reaction chamber with the aid of an inert gas;

feeding a second reactant into the reaction space; and

removing excess second reactant from the reaction chamber with the aid of an inert gas.

13. The process according to claim 12 , wherein the second reactant is selected from hydrogen gas or hydrogen plasma.

14. The process according to claim 12 , wherein the second reactant is a nitrogen containing compound and the metal thin film is a metal nitride thin film.

15. The process of claim 14 , wherein the nitrogen containing compound is selected from the group consisting of ammonia, nitrogen plasma, nitrogen and hydrogen plasma, ammonia plasma, hydrazine, and/or hydrazine derivatives.

16. The process of claim 12 , wherein the metal thin film is an elemental metal thin film.

17. The process of claim 16 , wherein the second reactant is hydrogen or hydrogen plasma.

18. The process according to claim 12 , wherein the second reactant is a reactive carbon containing compound and the metal thin film is a metal carbide thin film.

19. The process according to claim 18 , wherein the carbon containing compound is a hydrocarbon.

20. The process according to claim 19 , wherein the hydrocarbon is selected from the group consisting of alkanes, alkenes, and alkynes.

21. The process according to claim 18 , wherein the carbon containing compound has a central atom selected from the group consisting of elements in group B, Al, Ga, In, Si, Ge, Sn, P, As, or S.

22. The process of claim 12 , wherein the thin film is a multicomponent thin film.

23. The process of claim 22 additionally comprising:

a) contacting a substrate with a vapor phase pulse of a third reactant, wherein the third reactant is a metal precursor;

b) removing excess third reactant;

c) contacting the said substrate with a vapor pulse of a fourth reactant; and

d) removing excess fourth reactant.