# US 11,999,877 B2 · Silicon nitride chemical mechanical polishing slurry with silicon nitride removal rate enhancers and methods of use thereof

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,999,877 B2
- Document ID: US11999877B2
- Status: Granted
- Kind: B2
- Application number: 17/689,236
- Filed: 2022-03-08
- Published: 2022-10-06
- Granted: 2024-06-04
- Earliest claimed: 2021-03-24
- Assignees: Fujimi Incorporated
- Applicants: Fujimi Incorporated
- Inventors: Jimmy Granstrom
- Web page: https://patentgrep.com/patent/US11999877B2

## CPC

- C09G 1/02: containing abrasives or grinding agents {(abrasives as such C09K3/14; polishing of semi-conductors H10P52/40)}
- C09K 3/1436: {Composite particles, e.g. coated particles}
- H10P 95/062: {involving a dielectric removal step}
- C09G: POLISHING COMPOSITIONS (French polish C09F11/00); SKI WAXES
- C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10

## Abstract

The present disclosure relates to relates to silicon nitride (SiN) chemical-mechanical polishing (CMP) compositions with SiN removal rate enhancers. The SiN CMP compositions increase the SiN polishing rate while suppressing the tetratethylorthosilicate (TEOS) polishing rate, thus providing a high SiN/TEOS selectivity ratio and reducing any defects on the surfaces of polished substrates.

## Claims

### Claim 1

A polishing composition comprising an abrasive, a SiN removal rate enhancer, a pH adjusting agent, and water, wherein
the abrasive is anion-modified silica wherein a surface of the anion-modified silica has sulfonic acid groups covalently attached;
the SiN removal rate enhancer is a substituted 5- or 6-membered heterocycle, wherein the heterocyclic ring comprises at least two nitrogen atoms and the heterocycle is substituted with at least one group selected from —NH2 and —SH; and
the polishing composition has a pH from about 4 to about 6.

### Claim 2 (depends on 1)

The polishing composition of claim 1, wherein the electrical conductivity from greater than zero to about 0.25 mS/cm.

### Claim 3 (depends on 1)

The polishing composition of claim 1, wherein the SiN removal rate enhancer is monosubstituted with a —NH2 or —SH.

### Claim 4 (depends on 3)

The polishing composition of claim 3, wherein the SiN removal rate enhancer is a triazole.

### Claim 5 (depends on 3)

The polishing composition of claim 3, wherein the SiN removal rate enhancer is a pyrazine.

### Claim 6 (depends on 3)

The polishing composition of claim 3, wherein the SiN removal rate enhancer is selected from the group consisting of 3-mercapto-1,2,4-triazole, 3-amino-1,2,4-triazole, aminopyrazine, and combinations thereof.

### Claim 7 (depends on 6)

The polishing composition of claim 6, wherein the SiN removal rate enhancer is 3-mercapto-1,2,4-triazole.

### Claim 8 (depends on 1)

The polishing composition of claim 1, wherein the abrasive has a negative zeta potential in a range from about −30 mV to about −50 mV.

### Claim 9 (depends on 1)

The polishing composition of claim 1, further comprising a sulfonic acid present in a concentration from about 0.0001 wt % to about 0.005 wt %.

### Claim 10 (depends on 9)

The polishing composition of claim 9, wherein the sulfonic acid is naphthalene sulfonic acid, sodium salt.

### Claim 11 (depends on 1)

The polishing composition of claim 1, wherein the polishing composition has a SiN:TEOS removal rate selectivity ratio of at least 40.

### Claim 12 (depends on 1)

A method for polishing a substrate, the method comprising the steps of:
a) providing the polishing composition of claim 1;
b) providing a substrate, wherein the substrate comprises a silicon nitride layer; and
c) polishing the substrate with the polishing composition to provide a polished substrate.

### Claim 13 (depends on 12)

The method of claim 12, wherein the substrate is a semiconductor.

### Claim 14 (depends on 12)

The method of claim 12, wherein the substrate further comprises a silicon oxide layer.

### Claim 15 (depends on 14)

The method of claim 14, wherein the method results in a SiN:TEOS removal rate selectivity ratio of greater than about 40.