Integration of ALD tantalum nitride and alpha-phase tantalum for copper metallization application

• US 20030124262A1
• Filed: 10/25/2002
• Published: 07/03/2003
• Est. Priority Date: 10/26/2001
• Status: Abandoned Application

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Xi, Ming, Zhang, Hong, Chung, Hua, Chen, Ling, Ku, Vincent, Seutter, Sean M., Yang, Michael X., Ouye, Alan, Wu, Dien-Yeh, Nakashima, Norman, Chin, Barry
• Application Number:
  US10/281,386
• Publication Number:
  US 20030124262A1
• Time in Patent Office: Days
• US Class Current: 427/404
• CPC Class Codes: C23C 16/34 Nitrides C23C16/303 takes precedence
• CPC Class Codes: C23C 16/4411 Cooling of the reaction chamber walls C23C16/45572 takes precedence
• CPC Class Codes: C23C 16/4412 Details relating to the exhausts, e.g. pumps, filters, scrubbers, particle traps
• CPC Class Codes: C23C 16/45504 Laminar flow
• CPC Class Codes: C23C 16/45508 Radial flow
• CPC Class Codes: C23C 16/45512 Premixing before introduction in the reaction chamber
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]
• CPC Class Codes: C23C 16/45544 characterized by the apparatus
• CPC Class Codes: C23C 16/45563 Gas nozzles
• CPC Class Codes: C23C 16/45582 Expansion of gas before it reaches the substrate
• CPC Class Codes: H01L 21/28562 Selective deposition
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76846 Layer combinations
• CPC Class Codes: H01L 21/76871 Layers specifically deposited to enhance or enable the nucleation of further layers, i.e. seed layers

Abstract

A method for forming a metal interconnect on a substrate is provided. In one aspect, the method comprises depositing a refractory metal containing barrier layer having a thickness that exhibits a crystalline like structure and is sufficient to inhibit atomic migration on at least a portion of a metal layer by alternately introducing one or more pulses of a metal-containing compound and one or more pulses of a nitrogen-containing compound; depositing a seed layer on at least a portion of the barrier layer; and depositing a second metal layer on at least a portion of the seed layer.

Claims

1. A method for forming a metal interconnect on a substrate, comprising:

depositing a refractory metal containing barrier layer having a thickness that exhibits a crystalline like structure and is sufficient to inhibit atomic migration on at least a portion of a metal layer by alternately introducing one or more pulses of a metal-containing compound and one or more pulses of a nitrogen-containing compound;

depositing a seed layer on at least a portion of the barrier layer; and

depositing a second metal layer on at least a portion of the seed layer.

2. The method of claim 1, wherein the refractory metal containing barrier comprises tantalum nitride.

3. The method of claim 1, wherein a grain growth of the metal layer continues across the barrier layer into the second metal layer.

4. The method of claim 1, wherein each pulse is repeated until the refractory metal containing barrier layer has a thickness less than about 20 angstroms.

6. The method of claim 1, wherein the refractory metal containing barrier layer has a thickness of about 10 angstroms.

7. The method of claim 1, wherein the alternate pulsing is repeated between about 10 and about 70 times to form the refractory metal nitride layer.

8. The method of claim 1, further comprising flowing a purge gas continuously during each pulse of the metal-containing compound and each pulse of the nitrogen-containing compound.

9. The method of claim 8, wherein the purge gas comprises argon, nitrogen, helium, or combinations thereof.

10. The method of claim 1, wherein each pulse of the metal-containing compound and the nitrogen-containing is separated by a time delay.

11. The method of claim 10, wherein each time delay is long enough for a volume of the metal-containing compound or a volume of the nitrogen-containing compound to adsorb onto the substrate surface.

12. The method of claim 11, wherein the time delay is long enough to remove non-adsorbed molecules from the substrate surface.

13. The method of claim 1, wherein the nitrogen-containing compound is selected from a group consisting of ammonia;

hydrazine;

methylhydrazine;

dimethylhydrazine;

t-butylhydrazine;

phenylhydrazine;

azoisobutane;

ethylazide;

derivatives thereof; and

combinations thereof.

14. The method of claim 1, wherein the metal-containing compound is selected from a group consisting of:

tetrakis (dimethylamino) titanium (TDMAT);

tetrakis (ethylmethylamino) titanium (TEMAT);

tetrakis (diethylamino) titanium (TDEAT);

titanium tetrachloride (TiCl₄);

titanium iodide (TiI₄);

titanium bromide (TiBr₄);

t-butylimino tris(diethylamino) tantalum (TBTDET);

pentakis (ethylmethylamino);

tantalum (PEMAT);

pentakis (dimethylamino) tantalum (PDMAT);

pentakis (diethylamino) tantalum (PDEAT);

t-butylimino tris(diethyl methylamino) tantalum(TBTMET);

t-butylimino tris(dimethyl amino) tantalum (TBTDMT);

bis(cyclopentadienyl) tantalum trihydride ((Cp)₂TaH₃);

bis(methylcyclopentadienyl) tantalum trihydride ((CpMe)₂TaH₃);

derivatives thereof; and

combinations thereof.

15. The method of claim 1, wherein the first and second metal layers each comprise tungsten, copper, or a combination thereof.

16. The method of claim 1, wherein the seed layer comprises a first seed layer deposited over the barrier layer and a second seed layer deposited over the first seed layer.

17. The method of claim 16, wherein the first seed layer comprises a copper alloy seed layer of the copper and a metal selected from the group consisting of aluminum, magnesium, titanium, zirconium, tin, and combinations thereof or wherein the first seed layer comprises a metal selected from the group consisting of aluminum, magnesium, titanium, zirconium, tin, and combinations thereof.

18. A method for forming a metal interconnect on a substrate, comprising:

depositing a first metal layer on a substrate surface;

depositing a titanium silicon nitride layer having a thickness less than about 20 angstroms over at least a portion of the first metal layer by alternately introducing one or more pulses of a titanium-containing compound, one or more pulses of a silicon-containing compound, and one or more pulses of a nitrogen-containing compound;

depositing a dual alloy seed layer; and

depositing a second metal layer on at least a portion of the dual alloy seed layer.

19. A method for forming a metal interconnect on a substrate, comprising:

depositing a bilayer barrier having a thickness less than about 20 angstroms on at least a portion of a metal layer, the bilayer barrier comprising;

a first layer of tantalum nitride deposited by alternately introducing one or more pulses of a tantalum-containing compound and one or more pulses of a nitrogen-containing compound; and

a second layer of alpha phase tantalum;

depositing a dual alloy seed layer; and

depositing a second metal layer on at least a portion of the dual alloy seed layer.

20. A method for forming a metal interconnect on a substrate, comprising:

depositing a first metal layer on a substrate surface;

depositing a tantalum nitride barrier layer having a thickness less than about 20 angstroms on at least a portion of the first metal layer by alternately introducing one or more pulses of a tantalum-containing compound and one or more pulses of a nitrogen-containing compound;

depositing a dual alloy seed layer comprising copper and a metal selected from the group consisting of aluminum, magnesium, titanium, zirconium, tin, and combinations thereof; and

depositing a second metal layer on at least a portion of the dual alloy seed layer.