Composition and method for metal CMP

Patent metadata

Field	Value
Publication number	US-10968366-B2
Application number	US-201816208742-A
Country	US
Kind code	B2
Filing date	Dec 4, 2018
Priority date	Dec 4, 2018
Publication date	Apr 6, 2021
Grant date	Apr 6, 2021

Abstract

A chemical mechanical polishing composition for polishing a substrate includes a liquid carrier and cationic metal oxide abrasive particles dispersed in the liquid carrier. The cationic metal oxide abrasive particles have a surface modified with at least one compound consisting of a silyl group having at least one quaternary ammonium group. A method for chemical mechanical polishing a substrate including a metal layer includes contacting the substrate with the above described polishing composition, moving the polishing composition relative to the substrate, and abrading the substrate to remove a portion of the metal layer from the substrate and thereby polish the substrate.

First claim

The invention claimed is:

1. A chemical mechanical polishing composition comprising:
a liquid carrier;
cationic metal oxide abrasive particles dispersed in the liquid carrier, the cationic metal oxide abrasive particles having a surface modified with at least one compound comprising a silyl group represented by general formula (2) or general formula (3):
—Si(X) n -[L-CR 1 (OH)—C(R 2 ) 2 -A] 3-n   (2)

wherein X is the same or different and each represents a hydroxyl group, a hydrolyzable substituent, a non-hydrolyzable substituent, or a bond with an O—Si of another silyl group or the particle;
n is 0, 1, or 2;
L is a linkage group;
R 1 is a hydrogen atom or an alkyl group that contains an amino group, a hydroxyl group, or an unsaturated bond;
R 2 is the same or different, and each represents a hydrogen atom or an alkyl group that contains an amino group, a hydroxyl group, or an unsaturated bond; and
A is a quaternary ammonium group;

wherein X is the same or different and each represents a hydroxyl group, a hydrolyzable substituent, a non-hydrolyzable substituent, or a bond with an O—Si of another silyl group or the particle;
n′ is 0, 1, or 2;
L′ is a linkage group; and
A′ is a quaternary ammonium group;
wherein the metal oxide abrasive particles have an aggregation ratio in a range from about 1.5 to about 5.0, and wherein the cationic metal oxide abrasive particles have an isoelectric point greater than about 9.

2. The composition of claim 1 , wherein
the silyl group is represented by the general formula (2); and
L is —CH 2 CH 2 CH 2 OCH 2 —, R 1 and R 2 are H, and A is —N′R′R″R′″ wherein R′, R″, and R′″ are the same or different and include substantially any carbon containing compound.

3. The composition of claim 1 , wherein
the silyl group is represented by the general formula (3); and
L is —CH 2 CH 2 — and A′ is —N′R′R″R′″ wherein R′, R″, and R′″ are the same or different and include substantially any carbon containing compound.

4. The composition of claim 1 , wherein the liquid carrier is water.

5. The composition of claim 1 , wherein the metal oxide abrasive particles are silica particles.

6. The composition of claim 1 , wherein the metal oxide abrasive particles have a mean particle size in a range from about 30 to about 90 nm.

7. The composition of claim 1 , having a pH from about 6 to about 8.

8. The composition of claim 1 , wherein the cationic metal oxide abrasive particles comprise colloidal silica particles having a zeta potential of at least 20 mV at a pH of greater than 6.

9. The composition of claim 1 , comprising less than about 2 weight percent of the cationic metal oxide abrasive particles.

10. The composition of claim 1 , wherein the liquid carrier has a total dissolved silicon concentration of less than about 150 ppm.

11. The composition of claim 1 , wherein the liquid carrier has a residual silane concentration of less than about 100 ppm.

12. The composition of claim 1 , further comprising a hydrogen peroxide oxidizer and a metal corrosion inhibitor.

13. A chemical mechanical polishing composition comprising:
a liquid carrier;
cationic metal oxide abrasive particles dispersed in the liquid carrier, the cationic metal oxide abrasive particles having a surface modified with at least one compound comprising a silyl group represented by general formula (2) or general formula (3):
—Si(X) n -[L-CR 1 (OH)—C(R 2 ) 2 -A] 3-n   (2)

wherein X is the same or different and each represents a hydroxyl group, a hydrolyzable substituent, a non-hydrolyzable substituent, or a bond with an O—Si of another silyl group or the particle;
n is 0, 1, or 2;
L is a linkage group;
R 1 is a hydrogen atom or an alkyl group that contains an amino group, a hydroxyl group, or an unsaturated bond;
R 2 is the same or different, and each represents a hydrogen atom or an alkyl group that contains an amino group, a hydroxyl group, or an unsaturated bond; and
A is a quaternary ammonium group;

wherein X′ is the same or different and each represents a hydroxyl group, a hydrolyzable substituent, a non-hydrolyzable substituent, or a bond with an O—Si of another silyl group or the particle;
n′ is 0, 1, or 2;
L′ is a linkage group; and
A′ is a quaternary ammonium group;
wherein the metal oxide abrasive particles have an aggregation ratio in a range from about 1.5 to about 5.0, further comprising a triazole pyridine compound and having a pH in a range from about 6 to about 8.

14. A chemical mechanical polishing composition comprising:
a liquid carrier;
cationic metal oxide abrasive particles dispersed in the liquid carrier, the cationic metal oxide abrasive particles having a surface modified with at least one compound comprising a silyl group represented by the general formula:
—Si(X) n -[L-O—R-A] 3-n   (1)

wherein X is the same or different and each represents a hydroxyl group, a hydrolyzable substituent, a non-hydrolyzable substituent, or a bond with an O—Si of another silyl group or the particle;
n is 0, 1, or 2;
L is a linkage group;
O is an oxygen heteroatom;
R is an alkyl group that contains an amino group, a hydroxyl group, or an unsaturated bond; and
A is a quaternary ammonium group;
wherein the liquid carrier is water and the metal oxide abrasive particles have a mean particle size in a range from about 30 to about 90 nm.

15. The composition of claim 14 , wherein L is —CH 2 CH 2 CH 2 —, R is —CH 2 CH(OH)CH 2 —, and A is —N + R′R″R′″ wherein R′, R″, and R′″ are the same or different and include substantially any carbon containing compound.

16. The composition of claim 14 , having a pH from about 6 to about 8 and wherein the wherein the cationic metal oxide abrasive particles comprise colloidal silica particles having a zeta potential of at least 20 mV.

17. The composition of claim 14 , comprising less than about 2 weight percent of the metal oxide abrasive particles.

18. The composition of claim 14 , wherein the liquid carrier has a total dissolved silicon concentration of less than about 150 ppm.

19. The composition of claim 14 , wherein the liquid carrier has a residual silane concentration of less than about 100 ppm.

20. The composition of claim 14 , further comprising a hydrogen peroxide oxidizer and a metal corrosion inhibitor.

21. The composition of claim 14 , further comprising a triazole pyridine compound and having a pH in a range from about 6 to about 8.

Assignees

• Cabot Microelectronics Corp
• Cmc Mat Inc

Inventors

• Kraft Steven
• Hung Low Fernando
• Clingerman Daniel
• Ivanov Roman A
• Grumbine Steven

Classifications

• H10P52/403

  of conductive or resistive materials · CPC title

• H10P95/062

  involving a dielectric removal step · CPC title

• C09K3/1463

  Aqueous liquid suspensions · CPC title

• C09G1/02 Primary

  containing abrasives or grinding agents {(abrasives as such C09K3/14; polishing of semi-conductors H10P52/40)} · CPC title

• B24B57/02

  for feeding of fluid, sprayed, pulverised, or liquefied grinding, polishing or lapping agents · CPC title