POLISHING SLURRY COMPOSITION

• US 20170022391A1
• Filed: 07/08/2016
• Published: 01/26/2017
• Est. Priority Date: 07/23/2015
• Status: Active Grant

• Current Assignee: Kctech Co., Ltd.
• Original Assignee: KC Tech Company Limited
• Inventors: CHOI, Dong Kyu, YOON, Young Ho, KONG, Hyun Goo, HWANG, Jin Sook, PARK, Han Teo
• Granted Patent: US 10,077,381 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C09G 1/02 containing abrasives or grinding agents abrasives as such C09K3/14; polishing of semi-conductors H01L
• CPC Class Codes: C23F 3/06 with acidic solutions

Abstract

A polishing slurry composition is provided. The polishing slurry composition includes at least two types of abrasive particles among first abrasive particles, second abrasive particles, and third abrasive particles, and an oxidizer. A peak-to-valley roughness Rpv decreases when a contact area between the abrasive particles and a tungsten-containing film increases.

Claims

1. A polishing slurry composition comprising:

at least two types of abrasive particles among first abrasive particles, second abrasive particles, and third abrasive particles; and

an oxidizer,

wherein a peak-to-valley roughness Rpv decreases when a contact area between the abrasive particles and a tungsten-containing film increases.

2. The polishing slurry composition of claim 1, wherein the contact area between the abrasive particles and the tungsten-containing film ranges from 0.5 to 0.9, and is calculated by the following equation:

A=C₀^1/3·

φ

<sup>−

1/3</sup>

wherein A denotes the contact area, C₀ denotes a concentration of the abrasive particles in % by weight (wt %), and φ

denotes a diameter of an abrasive particle in nanometers (nm).

3. The polishing slurry composition of claim 1, wherein the polishing slurry composition satisfies a removal ratio of 35% to 70% calculated by the following equation:

4. The polishing slurry composition of claim 3, wherein when the contact area between the abrasive particles and the tungsten-containing film is 0.5 or more and 0.7 or less, the removal ratio ranges from 35% or more and less than 43%,

when the contact area between the abrasive particles and the tungsten-containing film exceeds 0.7 and is 0.9 or less, the removal ratio is 43% or more and 70% or less, and

the contact area is calculated by the following equation:

A=C₀^1/3·

φ

<sup>−

1/3</sup>

wherein A denotes the contact area, C₀ denotes a concentration of the abrasive particles in wt %, and φ

denotes a diameter of an abrasive particle in nm.

5. The polishing slurry composition of claim 1, wherein the polishing slurry composition is used to improve topography of the tungsten-containing film.

6. The polishing slurry composition of claim 1, wherein the first abrasive particles have a primary particle size of 20 nm or more to less than 45 nm and a secondary particle size of 30 nm or more to less than 100 nm,

the second abrasive particles have a primary particle size of 45 nm or more to less than 130 nm and a secondary particle size of 100 nm or more to less than 180 nm,

the third abrasive particles have a primary particle size of 130 nm or more to less than 250 nm and a secondary particle size of 180 nm or more to less than 500 nm,

the first abrasive particles are present in an amount of 10 wt % to 60 wt % in all the abrasive particles,

the second abrasive particles are present in an amount of 10 wt % to 60 wt % in all the abrasive particles, and

the third abrasive particles are present in an amount of 10 wt % to 60 wt % in all the abrasive particles.

7. The polishing slurry composition of claim 1, wherein the polishing slurry composition is hydrogen peroxide-free or comprises less than 1 wt % of hydrogen peroxide.

8. The polishing slurry composition of claim 1, wherein a peak-to-valley roughness Rpv of a surface of a tungsten-containing film polished using the polishing slurry composition is 100 nm or less, and a roughness of the surface is 10 nm or less.

9. A tungsten polishing slurry composition for polishing tungsten, the tungsten polishing slurry composition comprising:

at least two types of abrasive particles among first abrasive particles, second abrasive particles, and third abrasive particles,

wherein a specific surface area of the abrasive particles satisfies the following conditional expression;

20 m²/g≦

(T_A×

K_A)+(T_B×

K_B)+(T_C×

K_C)≦

100 m²/g,

wherein T_A, T_B and T_C denote a specific surface area of the first abrasive particles, a specific surface area of the second abrasive particles, and a specific surface area of the third abrasive particles, respectively, one of the specific surface areas T_A, T_B, and T_C has a value of “

0,”

K_A, K_B and K_C denote a ratio of an amount of the first abrasive particles to a total amount of the abrasive particles, a ratio of an amount of the second abrasive particles to the total amount of the abrasive particles and a ratio of an amount of the third abrasive particles to the total amount of the abrasive particles, respectively, and 0≦

K_A<

1, 0≦

K_B<

1, and 0≦

K_C<

1 are satisfied.

10. The tungsten polishing slurry composition of claim 9, wherein the first abrasive particles, the second abrasive particles or the third abrasive particles each have a specific surface area of 10 square meters per gram (m²/g) to 120 m²/g.

11. The tungsten polishing slurry composition of claim 9, wherein the first abrasive particles have a specific surface area of 70 m²/g to 120 m²/g,

the second abrasive particles have a specific surface area of 25 m²/g to 70 m²/g, and

the third abrasive particles have a specific surface area of 10 m²/g to 25 m²/g.

12. The tungsten polishing slurry composition of claim 9, wherein the first abrasive particles are present in an amount of 10 wt % to 70 wt % in all the abrasive particles,

the second abrasive particles are present in an amount of 10 wt % to 70 wt % in all the abrasive particles, and

the third abrasive particles are present in an amount of 10 wt % to 70 wt % in all the abrasive particles.

13. The tungsten polishing slurry composition of claim 9, wherein a component of a portion of each of the abrasive particles is substituted with a metal ion.

14. The tungsten polishing slurry composition of claim 13, wherein the metal ion has a tetrahedral coordination, and

the metal ion comprises at least one selected from the group consisting of iron (Fe), aluminum (Al), arsenic (As), gallium (Ga), boron (B), beryllium (Be), cobalt (Co), chromium (Cr), hafnium (Hf), indium (In), magnesium (Mg), manganese (Mn), nickel (Ni), phosphorus (P), titanium (Ti), vanadium (V), zinc (Zn) and zirconium (Zr).

15. The tungsten polishing slurry composition of claim 13, wherein the abrasive particles are colloidal silica abrasive particles, the metal ion is an Fe ion, and a silicon (Si) ion of a portion of a surface of each of the colloidal silica abrasive particles is substituted with the Fe ion.

16. The tungsten polishing slurry composition of claim 9, wherein a planarization degree of a surface of a tungsten-containing wafer polished using the tungsten polishing slurry composition is 5% or less.

17. The tungsten polishing slurry composition of claim 9, wherein a peak-to-valley roughness Rpv of a surface of a tungsten-containing wafer polished using the tungsten polishing slurry composition is 100 nm or less, and a roughness of the surface is 10 nm or less.

18. The tungsten polishing slurry composition of claim 9, wherein the tungsten polishing slurry composition is used to improve topography of a tungsten-containing wafer.