Polishing apparatus for a substrate and polishing method for a substrate using the same

1 . A polishing apparatus for a substrate, comprising:

a polishing pad formed of a light-transmitting material;

a platen on which the polishing pad is disposed on an upper surface thereof, the platen having a groove portion in a region overlapping the polishing pad, and being rotatably installed in one direction;

a slurry supply unit comprising at least one nozzle and configured to supply a slurry containing photocatalyst particles excited by light of a predetermined wavelength band to the polishing pad;

a light source accommodated in the groove portion of the platen, and configured to emit the light of the predetermined wavelength band;

a light-transmitting cover covering the light source and contacting an upper surface of the light source;

a conditioner installed on the polishing pad to be spaced apart from the slurry supply unit in the one direction, and configured to polish a surface of the polishing pad; and

a polishing head installed on the polishing pad to be spaced apart from the conditioner in the one direction, and configured to rotate the substrate in contact with the polishing pad,

wherein the upper surface of the light-transmitting cover is at the same level as an upper surface of the platen, and

wherein a lower surface of the polishing pad contacts an upper surface of the light-transmitting cover and the upper surface of the platen,

wherein the light source has a disk shape having a first diameter,

wherein the light-transmitting cover has a disk shape having a second diameter larger than the first diameter, and

wherein the platen has a disk shape having a third diameter larger than the second diameter.

2 . The polishing apparatus of claim 1 , wherein the light source is configured to emit ultraviolet light having a wavelength range of 234 nm to 365 nm.

3 . The polishing apparatus of claim 2 , wherein the photocatalyst particles include one or more of TiO 2 , ZnO, ZrO 2 , CdSe, WO 3 /TiO 2 , and Al 2 O 3 /ZrO 2 , and mixtures thereof.

4 . The polishing apparatus of claim 1 , wherein the light source is configured to emit visible light.

5 . The polishing apparatus of claim 4 , wherein the photocatalyst particles include one or more of Au/TiO 2 , TiO 2 /SeO 2 , and TiO 2 /SiO 2 , and mixtures thereof.

6 . The polishing apparatus of claim 1 , wherein the slurry further comprises an abrasive.

7 . The polishing apparatus of claim 1 , wherein the photocatalyst particles are an abrasive of the slurry.

8 . The polishing apparatus of claim 1 ,

wherein the light source comprises a plurality of light source elements,

wherein each of the plurality of light source elements has a ring shape having a center common to a center of the platen, and

wherein the plurality of light source elements are arranged concentrically.

9 . The polishing apparatus of claim 8 , wherein each of the plurality of light source elements is configured to emit different amounts of light.

10 . The polishing apparatus of claim 1 , wherein the light-transmitting cover comprises at least one of soft glass, fused silica, and fused quartz.

11 . The polishing apparatus of claim 1 , further comprising:

a power supply configured to apply power to the light source; and

a controller configured to control the power applied by the power supply to the light source to adjust an amount of the OH radicals generated from the photocatalyst particles in the slurry.

12 . A polishing apparatus for a substrate, comprising:

a polishing pad having at least one region formed of a light-transmitting material;

a platen on which the polishing pad is disposed on an upper surface thereof, the platen having a groove portion in a region overlapping the polishing pad, and being rotatably installed in one direction;

a light source accommodated in the groove portion of the platen, and configured to emit light of a predetermined wavelength band to the at least one region of the polishing pad;

a light-transmitting cover covering the light source and contacting an upper surface of the light source;

a slurry supply unit comprising at least one nozzle and configured to supply a slurry containing photocatalyst particles excited by the light of the predetermined wavelength band to the polishing pad; and

a polishing head installed on the polishing pad to be spaced apart from the slurry supply unit in the one direction, and configured to rotate the substrate in contact with the polishing pad,

wherein the upper surface of the light-transmitting cover is at the same level as an upper surface of the platen, and

wherein a lower surface of the polishing pad contacts an upper surface of the light-transmitting cover and the upper surface of the platen,

wherein the light source has a disk shape having a first diameter,

wherein the light-transmitting cover has a disk shape having a second diameter larger than the first diameter, and

wherein the platen has a disk shape having a third diameter larger in the second diameter.

13 . The polishing apparatus of claim 12 , wherein the polishing pad is entirely formed of a light transmitting material.

14 . The polishing apparatus of claim 12 ,

wherein the polishing pad comprises a first region and a second region, having different light transmittances, and

wherein the first region is the at least one region.

15 . The polishing apparatus of claim 12 , wherein, in the slurry, when the light of the predetermined wavelength band is irradiated, the photocatalyst particles are excited to generate OH radicals.

16 . A polishing apparatus for a substrate, comprising:

a platen on which a polishing pad formed of a light-transmitting material is disposed on an upper surface thereof, and rotatably installed in one direction;

a light source accommodated in a groove portion formed on an upper surface of the platen, and configured to emit light of a predetermined wavelength band toward the polishing pad;

a light-transmitting cover covering the light source and contacting an upper surface of the light source; and

a slurry supply unit comprising at least one nozzle and configured to supply a slurry containing photocatalyst particles excited by the light of the predetermined wavelength band to the polishing pad,

wherein the upper surface of the light-transmitting cover is at the same level as an upper surface of the platen, and

wherein a lower surface of the polishing pad contacts an upper surface of the light-transmitting cover and the upper surface of the platen,

wherein the light source has a disk shape having a first diameter,

wherein the light-transmitting cover has a disk shape having a second diameter larger than the first diameter, and

wherein the platen has a disk shape having a third diameter larger than the second diameter.

17 . The polishing apparatus of claim 16 , wherein, in the slurry, when the light of the predetermined wavelength band is irradiated, the photocatalyst particles are excited to generate OH radicals.

18 . The polishing apparatus of claim 17 , further comprising:

a power supply device configured to apply power to the light source; and

a controller configured to control the power applied by the power supply device to the light source.

19 . The polishing apparatus of claim 18 , wherein the controller is configured to control the power supplied to the light source to adjust an amount of the OH radicals generated from the photocatalyst particles in the slurry.