Polishing pad, process for preparing the same, and process for preparing a semiconductor device using the same

Patent metadata

Field	Value
Publication number	US-11298795-B2
Application number	US-202017002468-A
Country	US
Kind code	B2
Filing date	Aug 25, 2020
Priority date	Oct 29, 2019
Publication date	Apr 12, 2022
Grant date	Apr 12, 2022

Abstract

Embodiments relate to a polishing pad for use in a chemical mechanical planarization (CMP) process of semiconductors, a process for preparing the same, and a process for preparing a semiconductor device using the same. In the polishing pad according to the embodiment, the size (or diameter) and distribution of a plurality of pores are adjusted, whereby the polishing performance such as polishing rate and within-wafer non-uniformity can be further enhanced.

First claim

The invention claimed is:

1. A polishing pad, which comprises a polishing layer comprising a plurality of pores,
wherein the total area of the pores per unit area (mm 2 ) of the polishing surface is 40% to 60%,
the D q value represented by the following Equation 1 is 5 μm to 15 μm,
the D sk value represented by the following Equation 2 is greater than 0.3 to less than 1, and
the D ku value represented by the following Equation 3 is greater than 1 to less than 5:

D
q

=

∑

i
=
1

n

⁢

⁢

d
i
2

n

[

Equation
⁢

⁢
1

]

D
sk

=

1

nD
q
3

⁢

(

∑

i
=
1

n

⁢

⁢

d
i
3

)

[

Equation
⁢

⁢
2

]

D
ku

=

1

nD
q
4

⁢

(

∑

i
=
1

n

⁢

⁢

d
i
4

)

[

Equation
⁢

⁢
3

]

in Equations 1 to 3, d is a value obtained by subtracting the number average diameter of the plurality of pores from each pore diameter, and n is the total number of pores per unit area (mm 2 ).

2. The polishing pad of claim 1 , wherein the D q value is 7 μm to 14 μm, the D sk value is greater than 0.4 to less than 1, and the D ku value is greater than 2 to less than 5.

3. The polishing pad of claim 1 , wherein n is 700 to 2,500, and d is −30 to 60.

4. The polishing pad of claim 1 , wherein, in the diameter distribution of the plurality of pores based on the polishing surface, the number average diameter of the plurality of pores is 15 μm to 25 μm, and the pore diameter at the maximum peak is 10 μm to 150 μm.

5. The polishing pad of claim 4 , wherein the pore diameter at the maximum peak is greater than the number average diameter of the plurality of pores by 5 μm to 30 μm.

6. The polishing pad of claim 1 , which has a polishing rate of 720 Å/min to 860 Å/min for a tungsten layer and a polishing rate of 2,750 Å/min to 3,300 Å/min for an oxide layer.

Assignees

• Skc Solmics Co Ltd

Inventors

• Yun Sunghoon
• Heo Hye Young
• Seo Jang Won

Classifications

• H10P52/403

  of conductive or resistive materials · CPC title

• B24B37/26 Primary

  characterised by the shape of the lapping pad surface, e.g. grooved · CPC title

• B24D11/00

  Constructional features of flexible abrasive materials; Special features in the manufacture of such materials · CPC title

• B24B47/12

  by mechanical gearing or electric power (B24B47/16 takes precedence) · CPC title

• B24D11/003 Primary

  without embedded abrasive particles (B24D11/005 takes precedence) · CPC title