US 12,734,640 B2Granted

Method for refreshing polishing pad and method for manufacturing semiconductor device using the same

AssigneesEnpulse Co., Ltd., SK hynix Inc.

InventorsSung Hoon Yun, Jang Won Seo, Jae Gon Choi

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Abstract

The present disclosure relates to a method for refreshing a polishing pad, and, through increasing a useful life of a polishing pad used in a polishing process, is capable of reducing the amount of discarded polishing pad, and significantly enhancing polishing efficiency by shortening the time required to replace the polishing pad. In addition, a method for manufacturing a semiconductor device is a manufacturing process using the method for refreshing a polishing pad, wherein a polishing pad having the period of usage ended is reusable by having polishing performance equivalent to a new polishing pad, and process efficiency may be enhanced by reducing the number of replacements of polishing pads.

Claims9

Dependent claims

A method for refreshing a polishing pad, the method comprising:

supplying water vapor to the polishing pad,
wherein the polishing pad includes a polyurethane polishing layer provided with a polishing surface;
the polishing layer includes a plurality of pores;
and
the polishing surface includes a fine concave portion derived from the plurality of pores,
wherein the supplying water vapor to the polishing pad is initiated in response to the polishing pad corresponding to any one or more of the following conditions i) to iv):
i) the polishing surface having ISO 25178 three-dimensional arithmetic mean surface roughness (Sa) of 6 pm or less;
ii) the polishing surface having an ISO 25178 reduced peak height (Spk) of 5 pm or less;
iii) the polishing surface having an ISO 25178 reduced valley depth (Svk) of 16 pm or less,
iv) the polishing pad exhibits a removal rate of 1,500 Å/min to 1,800 Å/min and within-wafer nonuniformity (WIWNU) of 8% to 9% in a process of polishing a silicon oxide film for 60 seconds while calcined ceria slurry is supplied at a rate of 200 ml/minute, a semiconductor substrate, a subject to be polished, is pressurized with a load of 3.5 psi, the polishing pad has a rotation speed of 93 rpm and the semiconductor substrate has a rotation speed of 87 rpm,
wherein the supplying of water vapor to the polishing pad is conducted while the polishing pad is installed on a surface plate,
wherein the supplying of water vapor to the polishing pad is supplying water vapor of 60° C. to 120° C.,
wherein, after the supplying of water vapor to the polishing pad, the polishing layer has a polishing restoration index (PRI) represented by the following Equation 2 of 3.10 to 3.80:
P
⁢
R
⁢
I
=
(
S
pk
+
S
vk
)
S
a
[
Equation
⁢
2
]
wherein,
Sa is an ISO 25178 three-dimensional arithmetic mean surface roughness of the polishing surface;
Spk is an ISO 25178 reduced peak height of the polishing surface;
and
Svk is an ISO 25178 reduced valley depth of the polishing surface.

35 more elements

A method for manufacturing a semiconductor device, the method comprising:

installing a polishing pad including a polyurethane polishing surface on a surface plate;
arranging a surface to be polished of a subject to be polished to be in contact with the polishing surface, and then polishing the subject to be polished while rotating the polishing pad and the subject to be polished relative to each other under a pressurized condition;
and
supplying water vapor to the polishing surface of the polishing pad,
wherein the supplying water vapor to the polishing pad, is initiated in response to the polishing pad corresponding to any one or more of the following conditions i) to iv):
i) the polishing surface having ISO 25178 three-dimensional arithmetic mean surface roughness (Sa) of 6 pm or less;
ii) the polishing surface having an ISO 25178 reduced peak height (Spk) of 5 pm or less;
iii) the polishing surface having an ISO 25178 reduced valley depth (Svk) of 16 pm or less;
iv) the polishing pad exhibits a removal rate of 1,500 Å/min to 1,800 Å/min and within-wafer nonuniformity (WIWNU) of 8% to 9% in a process of polishing a silicon oxide film for 60 seconds while calcined ceria slurry is supplied at a rate of 200 ml/minute, a semiconductor substrate, a subject to be polished, is pressurized with a load of 3.5 psi, the polishing pad has a rotation speed of 93 rpm and the semiconductor substrate has a rotation speed of 87 rpm,
wherein the supplying water vapor to the polishing surface of the polishing pad is conducted while the polishing pad is installed on the surface plate,
wherein the supplying of water vapor to the polishing surface of the polishing pad is supplying water vapor of 60° C. to 120° C.,
wherein, after the supplying of water vapor to the polishing pad, a polishing layer has a polishing restoration index (PRI) represented by the following Equation 2 of 3.10 to 3.80:
PRI
=
(
S
p
⁢
k
+
S
v
⁢
k
)
S
a
[
Equation
⁢
2
]
wherein,
Sa is an ISO 25178 three-dimensional arithmetic mean surface roughness of the polishing surface;
Spk is an ISO 25178 reduced peak height of the polishing surface;
and
Svk is an ISO 25178 reduced valley depth of the polishing surface.

34 more elements

Dependencies are inferred from the claim text.