Tungsten processing slurry with catalyst

Patent metadata

Field	Value
Publication number	US-2017190936-A1
Application number	US-201614988891-A
Country	US
Kind code	A1
Filing date	Jan 6, 2016
Priority date	Jan 6, 2016
Publication date	Jul 6, 2017
Grant date	—

Abstract

Described are compositions (e.g., slurries) useful in methods for chemical-mechanical processing (e.g. polishing or planarizing) a surface of a substrate that contains tungsten, the slurries containing abrasive particles, metal cation catalyst, phosphorus-containing zwitterionic compound, and optional ingredients such as oxidizer; also described are methods and substrates used or processed on combination with the compositions.

First claim

1 . A chemical mechanical processing composition comprising:
liquid carrier, abrasive particles, catalyst comprising:
metal cation, and
zwitterionic compound capable of forming a complex in the composition with the metal cation, the zwitterionic compound comprising a phosphorus-containing group having a negative charge in the composition, and a cationic group having a positive charge in the composition.

2 . A composition of claim 1 wherein the composition has a pH below 7 and the negative charge is at a phosphate, phosphinate, or phosphonate group.

3 . A composition of claim 1 wherein the positive charge is at a nitrogen atom.

4 . A composition of claim 1 wherein the zwitterionic compound has a structure according to Formula 1:

wherein:
R 1 and R 2 are independently selected from
a negatively-charged oxygen (−O − ), and
hydroxy (—OH), or
an organic radical connected to the phosphorus atom through a divalent oxygen,

such that at least one of R 1 and R 2 is a negatively-charged oxygen providing the negative charge;
n is zero or one;
L is a linking group; and
R 3 is an organic group that exhibits the positive charge.

5 . A composition of claim 4 wherein one of R 1 and R 2 is a negatively-charged oxygen providing the negative charge, and the other of R 1 and R 2 is —OH.

6 . A composition of claim 4 wherein one of R 1 and R 2 is a negatively-charged oxygen providing the negative charge, and the other of R 1 and R 2 is an organic radical R 4 connected to the phosphorus atom through a divalent oxygen:

wherein R 4 is a substituted or unsubstituted, saturated, branched, or straight alkyl radical.

7 . A composition of claim 4 wherein R 3 is an amine-functional organic group comprising a nitrogen atom that provides the positive charge.

8 . A composition of claim 7 wherein the amine-functional organic group is selected from —NH 3 + , a quaternary ammonium, and an aromatic heterocyclic amine.

9 . A composition of claim 4 wherein the amine-functional organic group is —NH 3 + , and L is a substituted or unsubstituted divalent alkylene.

10 . A composition of claim 9 wherein L is substituted, comprising substituents selected from a hydroxy group, a phosphate group, a phosphonate group, and combinations thereof.

11 . A composition of claim 4 wherein L and R 3 together form an organic radical that includes one or multiple saturated or aromatic ring structures.

12 . A composition of claim 11 wherein L and R 3 together form an organic radical that includes one or multiple heteroatom-containing, saturated or aromatic ring structures, and one or more of the ring structures contain a charged or uncharged heteroatom selected from oxygen and nitrogen.

13 . A composition of claim 12 wherein the organic radical includes an aromatic nitrogen-containing ring, and the nitrogen of the aromatic ring provides the positive charge.

14 . A composition of claim 1 wherein the zwitterionic compound is selected from: o-phosphoryl-ethanolamine, choline glycerophosphate, inosine monophosphate, alendronic acid, aminoethylphosphonic acid, phosphocholine.

15 . A composition of claim 1 wherein the metal cation is an iron cation.

16 . A composition of claim 1 wherein the metal cation is derived from a soluble metal salt.

17 . A composition of claim 16 wherein the metal salt is iron nitrate nonahydrate.

18 . A composition of claim 16 comprising
from 0.001 to 0.2 weight percent of the metal salt, and
from 0.001 to 0.5 weight percent of the zwitterionic compound.

19 . A composition of claim 1 wherein the abrasive particles are colloidal silica particles.

20 . A composition of claim 1 comprising from about 0.5 to about 4 weight percent silica abrasive particles.

21 . A composition of claim 19 wherein the abrasive particles exhibit a positive charge of at least 6 millivolts, in the composition.

22 . A composition of claim 19 wherein the abrasive particles exhibit a permanent positive charge of at least 10 millivolts, in the composition.

23 . A method of chemical mechanical polishing a substrate that includes a surface comprising tungsten, the method comprising:
(a) contacting the substrate with a composition comprising:
abrasive particles, and
catalyst comprising:
metal cation, and
to zwitterionic compound capable of forming a complex in the composition with the metal cation, the zwitterionic compound comprising a phosphorus-containing group having a negative charge in the composition, and a cationic group having a positive charge in the composition,

(b) moving the composition relative to the substrate; and (c) abrading the substrate to remove a portion of the tungsten from the substrate.

24 . A method or claim 24 wherein the metal cation is iron cation, and
the zwitterionic compound has a structure according to Formula 1:

wherein:
R 1 and R 2 are independently selected from
a negatively-charged oxygen (−O − ), and
hydroxy (—OH), or
an organic radical connected to the phosphorus atom through a divalent oxygen,

such that at least one of R 1 and R 2 is a negatively-charged oxygen providing the negative charge;
n is zero or one;
L is a linking group; and
R 3 is exhibits the positive charge.

25 . A method or claim 24 wherein the zwitterionic compound is selected from: o-phosphoryl-ethanolamine, choline glycerophosphate, inosine monophosphate, alendronic acid, aminoethylphosphonic acid, phosphocholine.

Assignees

• Cabot Microelectronics Corp

Inventors

• Dockery Kevin P
• Huang Helin
• Carnes Matthew
• Whitener Glenn

Classifications

• H10P95/062

  involving a dielectric removal step · CPC title

• H10P52/403

  of conductive or resistive materials · CPC title

• C09K3/14 Primary

  Anti-slip materials; Abrasives {(products specifically intended for the fabrication of abrasive tools, blocks or papers, or for operations of the kind of sand-blasting and barrelling B24B31/14, B24C1/00; polishing compositions containing abrasive or grinding agents C09G1/02; friction compositions for brakes or clutches F16D69/02; polishing of semi-conductors H10P52/40)} · CPC title

• C09K3/1409

  Abrasive particles per se (preparation of diamond C01B32/25) · CPC title

• C09G1/04

  Aqueous dispersions (C09G1/02 takes precedence) · CPC title