ORGANOMETALLIC PRECURSORS FOR SEED/BARRIER PROCESSES AND METHODS THEREOF

• US 20080194105A1
• Filed: 02/14/2007
• Published: 08/14/2008
• Est. Priority Date: 02/14/2007
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Han, Joseph, Thompson, David, Dominguez, Juan, Lavoie, Adrien, Plombon, John, Peck, John, Simka, Harsono
• Granted Patent: US 7,851,360 B2
• Time in Patent Office: Days
• US Class Current: 438/681
• CPC Class Codes: C23C 16/18 from metallo-organic compounds
• CPC Class Codes: H01L 21/28562 Selective deposition
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76873 for electroplating
• CPC Class Codes: H01L 21/76874 for electroless plating

Abstract

Organometallic precursors and methods for deposition on a substrate in seed/barrier applications are herein disclosed. In some embodiments, the organometallic precursor is a ruthenium-containing, tantalum-containing precursor or combination thereof and may be deposited by atomic layer deposition, chemical vapor deposition and/or physical vapor deposition.

Claims

1. A method comprising:

forming a first layer comprising a material selected from the group consisting of a metal nitride, a metal carbide and a metal carbonitride on a substrate wherein the substrate includes at least one trench etched into a dielectric layer of the substrate;

forming a second layer on the first layer, the second layer comprising a material selected from the group consisting of ruthenium, tantalum and a combination thereof wherein (i) if a ruthenium layer is formed, forming comprises introducing a ruthenium-containing precursor selected from the group consisting of RuRR′

R″

, (Ring)RuL₂R, (Ring)RuLL′

R and (Ring)Ru[(η

³-R)(Ring)RuL₂] where R is a negatively charged two-electron donor;

L is a neutral two-electron donor;

η

³-R is a negatively charged chelating four-electron donor; and

Ring is an unfunctionalized or functionalized member of a group comprising cyclic dienes, pyrroles, dienes, boratabenzene and dienes containing heteroatoms;

or (ii) if a tantalum layer is formed, forming comprises introducing a tantalum-containing precursor selected from the group consisting of allylTa(CH₃)₃ where allyl is η

³C₃H₅;

(C₅H₅)₂TaR variations where R is amide or alkyl substituents;

Ta(borilidiene)-containing precursors;

(PR₃═

N)Ta variations where R is a hydrogen, an alkyl or a phenyl substituent and PR₃═

N is a phosphinamide ligand; and

selenium analogs thereof where R is a ring structure selected from the group consisting of cyclic dienes, mesityl, phenyl, tolyl, pyrroles and pyridyl; and

depositing a third layer comprising copper on the second layer and within the at least one trench.

2. The method of claim 1, further comprising, before depositing the third layer, cleaning the substrate by subjecting the substrate to a method selected from the group consisting of a wet chemical solution, a plasma and a plating bath.

3. The method of claim 1, wherein R is selected from the group consisting of an imide, a nitrile and an alkyldiene;

L is selected from the group consisting of carbon monoxide, nitric oxide, dienes, amine, nitrile, isocyanides and phosphanes; and

η

³-R is selected from the group consisting of allyls, azaallyls, amidinates and cyclobutadienes.

4. The method of claim 1, wherein the metal nitride, metal carbide or metal carbonitride layer is selected from the group consisting of tantalum nitride, tantalum carbide and tantalum carbonitride.

5. The method of claim 4, wherein the metal nitride, metal carbide or metal carbonitride layer is tantalum nitride formed from a composition having a general formula of R₃TaNR′

where R is an alkyl, hydrogen or an amide.

6. The method of claim 1, wherein the first layer is formed by an atomic layer deposition process.

7. The method of claim 1, wherein the second layer is formed by a method selected from the group consisting of an atomic layer deposition process, a chemical vapor deposition process and a physical vapor deposition process.

8. A method comprising:

introducing a semiconductor substrate in a reactor, wherein the semiconductor substrate includes at least one trench etched into a dielectric layer of the substrate;

forming a barrier layer on the substrate;

forming an adhesion layer on the barrier layer by introducing an organometallic precursor and a co-reactant into the reactor proximate to the semiconductor substrate to form the adhesion layer, wherein the precursor comprises a material selected from the group consisting of a ruthenium-containing material and a tantalum-containing material, (i) the ruthenium-containing material selected from the group consisting of RuRR′

R″

(Ring)RuL₂R, (Ring)RuLL′

R and (Ring)Ru[(η

³-R)(Ring)RuL₂] where R is a negatively charged two-electron donor;

L is a neutral two-electron donor;

η

³-R is a negatively charged chelating four-electron donor; and

Ring is an unfunctionalized or functionalized member of a group comprising cyclic dienes, pyrroles, dienes, boratabenzene and dienes containing heteroatoms; and

(ii) the tantalum-containing material selected from the group consisting of allylTa(CH₃)₃ where allyl is η

³C₃H₅;

(C₅H₅)₂TaR variations where R is amide or alkyl substituents;

Ta(borilidiene)-containing precursors;

(PR₃═

N)Ta variations where R is a hydrogen, an alkyl or a phenyl substituent and PR₃═

N is a phosphinamide ligand; and

selenium analogs thereof where R is a ring structure selected from the group consisting of cyclic dienes, mesityl, phenyl, tolyl, pyrroles and pyridyl; and

depositing a copper layer on the adhesion layer and in the at least one trench.

9. The method of claim 8, further comprising, before depositing the copper layer, cleaning the substrate by subjecting the substrate to one of a wet chemical solution, a plasma or a plating bath.

10. The method of claim 8, wherein the depositing of the copper layer comprises:

transferring the semiconductor substrate to a copper plating bath; and

depositing the copper layer on the adhesion layer using a plating process.

11. The method of claim 10, wherein the plating bath comprises an electroplating bath and the plating process comprises an electroplating process.

12. The method of claim 10, wherein the plating bath comprises an electroless plating bath and the plating process comprises an electroless plating process.

13. The method of claim 8, wherein the co-reactant comprises a material selected from the group consisting of atomic hydrogen, hydrogen gas, hydrogen plasma, sulfur, trimethylsilylazide, xenon, ammonia gas, diborane, methane, silane and plasma combinations thereof.

14. The method of claim 8, wherein the barrier layer is formed from a material selected from the group consisting of tantalum nitride, tantalum carbide and tantalum carbonitride.

15. The method of claim 14, wherein the barrier layer is tantalum nitride formed from a composition having a general formula of R₃TaNR′

where R is an alkyl, hydrogen or an amide and R′

is an anionically charged hydrocarbon group.

16. The method of claim 8, wherein the barrier layer is formed by atomic layer deposition and the adhesion layer is formed by a method selected from the group consisting of atomic layer deposition, chemical vapor deposition and physical vapor deposition.

17. The method of claim 8, wherein R is selected from the group consisting of an amide, a nitride and an alkyldiene;

L is selected from the group consisting of carbon monoxide, nitric oxide, dienes, amine, nitrile, isocyanides and phosphanes; and

η

³-R is selected from the group consisting of allyls, azaallyls, amidinates and cyclobutadienes.

18. The method of claim 8, wherein the adhesion layer is a homogenous mixture of a ruthenium-containing precursor and a tantalum-containing precursor.

19. A method comprising:

introducing a semiconductor substrate in a reactor, wherein the semiconductor substrate includes at least one trench etched into a dielectric layer of the substrate;

forming a barrier layer on the substrate;

pulsing an organometallic precursor into the reactor proximate to the semiconductor substrate, wherein the precursor comprises a material selected from the group consisting of a ruthenium-containing material and a tantalum-containing material, (i) the ruthenium-containing material selected from the group consisting of RuRR′

R″

, (Ring)RuL₂R, (Ring)RuLL′

R and (Ring)Ru[(η

³-R)(Ring)RuL₂] where R is a negatively charged two-electron donor;

L is a neutral two-electron donor; and

η

³-R is a negatively charged chelating four-electron donor; and

Ring is an unfunctionalized or functionalized member of a group comprising cyclic dienes, pyrroles, dienes, boratabenzene and dienes containing heteroatoms; and

(ii) the tantalum-containing material selected from the group consisting of allylTa(CH₃)₃ where allyl is η

³C₃H₅;

(C₅H₅)₂TaR variations where R is amide or alkyl substituents;

Ta(borilidiene)-containing precursors;

(PR₃═

N)Ta variations where R is a hydrogen, an alkyl or a phenyl substituent and PR₃═

N is a phosphinamide ligand; and

selenium analogs thereof where R is a ring structure selected from the group consisting of cyclic dienes, mesityl, phenyl, tolyl, pyrroles and pyridyl;

purging the reactor after the precursor pulse;

pulsing a co-reactant into the reactor proximate to the substrate, wherein the co-reactant reacts with the precursor to form a ruthenium- or tantalum-containing adhesion layer on the barrier layer;

purging the reactor after the co-reactant pulse; and

depositing a copper layer on the adhesion layer and in the at least one trench.

20. The method of claim 19, further comprising, before depositing the copper layer, cleaning the substrate by subjecting the substrate to one of a wet chemical solution, a plasma or a plating bath.

21. The method of claim 19, wherein the depositing of the copper layer comprises:

transferring the semiconductor substrate to a copper plating bath; and

depositing the copper layer on the adhesion layer using a plating process.

22. The method of claim 21, wherein the plating bath comprises an electroplating bath and the plating process comprises an electroplating process.

23. The method of claim 21, wherein the plating bath comprises an electroless plating bath and the plating process comprises an electroless plating process.

24. The method of claim 19, wherein the co-reactant comprises a material selected from the group consisting of atomic hydrogen, hydrogen gas, hydrogen plasma, sulfur, trimethylsilylazide, xenon gas, ammonia gas, diborane, methane, silane and plasma combinations thereof.

25. The method of claim 19, wherein the barrier layer is selected from the group consisting of tantalum nitride, tantalum carbide and tantalum carbonitride.

26. The method of claim 25, wherein the barrier layer is tantalum nitride formed from a composition having a general formula of R₃TaNR′

where R is an alkyl, hydrogen or an amide and R′

is an anionically charged hydrocarbon group.

27. The method of claim 19, wherein the barrier layer is formed by atomic layer deposition and the adhesion layer is formed by a method selected from the group consisting of atomic layer deposition, chemical vapor deposition and physical vapor deposition.

28. The method of claim 19, wherein R is selected from the group consisting of an amide, a nitride and an alkyldiene;

L is selected from the group consisting of carbon monoxide, nitric oxide, dienes, amine, nitrile, isocyanides and phosphanes; and

η

³-R is selected from the group consisting of allyls, azaallyls, amidinates and cyclobutadienes.

29. The method of claim 19, wherein the adhesion layer is a combination of a ruthenium-containing precursor and a tantalum-containing precursor.

30. The method of claim 29, wherein the adhesion layer is deposited by a process selected from the group consisting of (i) pulsing of a pre-mixed combination of a ruthenium-containing precursor and a tantalum-containing precursor, (ii) simultaneous pulsing of a ruthenium-containing precursor and a tantalum-containing precursor, and (iii) sequential pulsing of a ruthenium-containing precursor and a tantalum-containing precursor.