METHOD FOR FORMING Ta-Ru LINER LAYER FOR Cu WIRING

• US 20090155997A1
• Filed: 12/12/2007
• Published: 06/18/2009
• Est. Priority Date: 12/12/2007
• Status: Active Grant

• Current Assignee: ASM Japan K.K. (ASM International NV)
• Original Assignee: ASM Japan K.K. (ASM International NV)
• Inventors: SHINRIKI, Hiroshi, JEONG, Daekyun
• Granted Patent: US 7,655,564 B2
• Time in Patent Office: Days
• US Class Current: 438/653
• CPC Class Codes: C23C 16/045 Coating cavities or hollow spaces, e.g. interior of tubes; Infiltration of porous substrates
• CPC Class Codes: C23C 16/06 characterised by the deposition of metallic material
• CPC Class Codes: C23C 16/45542 Plasma being used non-continuously during the ALD reactions
• CPC Class Codes: H01L 21/28562 Selective deposition
• CPC Class Codes: H01L 21/76846 Layer combinations
• CPC Class Codes: H01L 21/76862 Bombardment with particles, e.g. treatment in noble gas plasmas; UV irradiation
• CPC Class Codes: H01L 21/76873 for electroplating
• CPC Class Codes: H01L 2221/1089 Stacks of seed layers
• CPC Class Codes: H01L 23/53238 Additional layers associated with copper layers, e.g. adhesion, barrier, cladding layers
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

A method of forming a Ta—Ru metal liner layer for Cu wiring includes: (i) conducting atomic deposition of Ta X times, each atomic deposition of Ta being accomplished by a pulse of hydrogen plasma, wherein X is an integer such that a surface of an underlying layer is not covered with Ta particles; (ii) after step (i), conducting atomic deposition of Ru Y times, each atomic deposition of Ru being accomplished by a pulse of hydrogen plasma, wherein Y is an integer such that the Ta particles are not covered with Ru particles; and (iii) repeating steps (i) and (ii) Z times, thereby forming a Ta—Ru metal liner layer on a Cu wiring substrate.

Claims

1. A method of forming a Ta—

Ru metal liner layer for Cu wiring, comprising;

(i) conducting atomic deposition of Ta X times, each atomic deposition of Ta being accomplished by a pulse of hydrogen plasma, wherein X is an integer such that a surface of an underlying layer is not covered with Ta particles;

(ii) after step (i), conducting atomic deposition of Ru Y times, each atomic deposition of Ru being accomplished by a pulse of hydrogen plasma, wherein Y is an integer such that the Ta particles are not covered with Ru particles; and

(iii) repeating steps (i) and (ii) Z times, thereby forming a Ta—

Ru metal liner layer on a Cu wiring substrate.

2. The method according to claim 1, wherein X is an integer of 1 or 2, and Y is an integer of 1 to 10.

3. The method according to claim 2, wherein X is an integer of 1, and Y is an integer of 2 to 6.

4. The method according to claim 1, wherein Z is an integer of 5 to 10.

5. The method according to claim 1, further comprising, after step (iii):

(iv) changing X, Y, and Z, and conducting steps (i) to (iii), thereby forming a second metal layer on the Ta—

Ru metal liner layer which is a first metal layer.

6. The method according to claim 5, further comprising, after step (iv):

(v) changing X, Y, and Z, and conducting steps (i) to (iii), thereby forming a third metal layer on the second metal liner layer.

7. The method according to claim 6, wherein Y for the second metal layer is zero, and X for the third metal layer is zero.

8. The method according to claim 7, where X, Y, and Z for the first metal layer are X1, Y1, and Z1, X, Y, and Z for the second metal layer are X2, Y2, and Z2, X, Y, and Z for the third metal layer are X3, Y3, and Z3, wherein X1=1, Y1=2-10, Z1=5-10, X2=1, Y2=0, Z2=30-60, X3=0, Y3=1, and Z3=50-100.

9. The method according to claim 6, wherein a ratio of X/Y for the second metal layer is greater than a ratio of X/Y for each of the first and third metal layers.

10. The method according to claim 6, wherein a ratio of X/Y for the third metal layer is smaller than a ratio of X/Y for each of the first and second metal layers.

11. The method according to claim 1, wherein step (i) comprises supplying a precursor vapor containing Ta into a reaction chamber and applying a pulse of hydrogen plasma to the vapor X times.

12. The method according to claim 11, wherein the precursor vapor containing Ta is at least one selected from the group consisting of TAIMATA (Tertiaryamylimidotris-(dimethylamido)tantalum), TBTDET (Ta(N-i-C4H9)[N(C2H5)2]3), and PDMAT (Ta[N(CH3)2]5).

13. The method according to claim 1, wherein step (ii) comprises supplying a precursor vapor containing Ru into a reaction chamber and applying a pulse of hydrogen plasma to the vapor Y times.

14. The method according to claim 13, wherein the precursor vapor containing Ru is β

-diketone-coordinated ruthenium compound.

15. The method according to claim 1, wherein the hydrogen plasma in steps (i) and (ii) is generated by applying RF power to a gas containing hydrogen.

16. The method according to claim 1, wherein the Cu wiring substrate on which the Ta—

Ru metal liner layer is formed is comprised of a metal film, a metal silicide film, and dielectric film.

17. A Ta—

Ru metal liner layer for Cu wiring, comprising a plurality of Ru-doped Ta atomic deposition layers formed on a Cu wiring substrate, each layer being formed by;

(i) conducting atomic deposition of Ta X times, each atomic deposition of Ta being accomplished by a pulse of hydrogen plasma, wherein X is an integer such that a surface of an underlying layer is not covered with Ta particles; and

(ii) after step (i), conducting atomic deposition of Ru Y times, each atomic deposition of Ru being accomplished by a pulse of hydrogen plasma, wherein Y is an integer such that the Ta particles are not covered with Ru particles.

18. The Ta—

Ru metal liner layer according to claim 17, wherein X is an integer of 1 or 2, and Y is an integer of 1 to 10.

19. The Ta—

Ru metal liner layer according to claim 18, wherein X is an integer of 1, and Y is an integer of 2 to 6.

20. The Ta—

Ru metal liner layer according to claim 17, wherein the number of Ru-doped Ta atomic deposition layers is Z which is an integer of 5 to 10.

21. The Ta—

Ru metal liner layer according to claim 17, further comprising a second metal layer formed on the Ru-doped Ta atomic deposition layers which constitute a first metal layer, said second metal layer being a plurality of atomic deposition layers, each atomic deposition layer being formed by conducting steps (i) and (ii) after changing X and Y.

22. The Ta—

Ru metal liner layer according to claim 21, further comprising a third metal layer formed on the second metal liner layer, said third metal layer being a plurality of atomic deposition layers, each atomic deposition layer being formed by conducting steps (i) and (ii) after changing X and Y.

23. The Ta—

Ru metal liner layer according to claim 22, wherein Y for the second metal layer is zero, and X for the third metal layer is zero.

24. The Ta—

Ru metal liner layer according to claim 23, wherein the number of atomic deposition layers is Z, and wherein X, Y, and Z for the first metal layer are X1, Y1, and Z1, X, Y, and Z for the second metal layer are X2, Y2, and Z2, X, Y, and Z for the third metal layer are X3, Y3, and Z3, wherein X1=1, Y1=2-10, Z1=5-10, X2=1, Y2=0, Z2=30-60, X3=0, Y3=1, and Z3=50-100.

25. The Ta—

Ru metal liner layer according to claim 22, wherein a ratio of X/Y for the second metal layer is greater than a ratio of X/Y for each of the first and third metal layers.

26. The Ta—

Ru metal liner layer according to claim 22, wherein a ratio of X/Y for the third metal layer is smaller than a ratio of X/Y for each of the first and second metal layers.

27. The Ta—

Ru metal liner layer according to claim 17, wherein the Cu wiring substrate on which the Ta—

Ru metal liner layer is formed is comprised of a metal film, a metal silicide film, and dielectric film.