Cleaning probe and megasonic cleaning apparatus having the same
A cleaning probe capable of providing uniform cleaning to an entire wafer while not damaging the edge portion of the wafer, and a megasonic cleaning apparatus having the cleaning probe are provided. The cleaning probe comprises a front portion located near the center of the wafer, a rear portion connected to a piezoelectric transducer, and a protrusion located between the rear portion and the front portion, located on an edge portion of the wafer, and having a larger cross section width than the front portion.
1. A megasonic cleaning apparatus comprising:
a cleaning vessel;
a rotation table located in the cleaning vessel and adapted to support a wafer placed on the rotation table;
a rotation axis connected to a bottom of the rotation table;
a motor connected to the rotation axis and configured to rotate the rotation table;
a cleaning probe located over the rotation table and the wafer and configured to transmit megasonic waves to a surface of the wafer via a cleaning fluid on the surface of the wafer;
a piezoelectric transducer connected to the cleaning probe and configured to generate megasonic waves; and,
a cleaning fluid supplying tube configured to supply cleaning fluid onto the wafer, wherein the cleaning probe comprises a rear portion connected to the piezoelectric transducer, a front portion located opposite the rear portion and located over the wafer, and a protrusion located between the rear portion and the front portion, and located over an edge portion of the wafer, wherein a cross section width of the protrusion is larger than a cross section width of the front portion.
2. The apparatus of claim 1 , wherein the cleaning probe further comprises:
a front connection portion connecting the protrusion and the front portion, wherein a cross section width of the front connection portion varies over a length of the front connection portion; and,
a rear connection portion connecting the protrusion and the rear portion, wherein a cross section width of the rear connection portion varies over a length of the rear connection portion.
3. The apparatus of claim 2 , wherein a boundary between the rear connection portion and the protrusion is located at a distance, measured from a center of the wafer, which is greater than or equal to a radius of the wafer.
4. The apparatus of claim 3 , wherein a boundary between the front connection portion and the protrusion is located at a distance, measured from the center of the wafer, which is greater than or equal to half of the radius of the wafer.
5. The apparatus of claim 4 , wherein a cross section of the protrusion is circular.
6. The apparatus of claim 5 , wherein a center of the cross section of the protrusion is on a same axis as a center of a cross section of the front portion.
7. The apparatus of claim 5 , wherein a center of the cross section of the protrusion is not on a same axis as a center of a cross section of the front portion.
8. The apparatus of claim 7 , wherein the center of the cross section of the protrusion is higher than the center of the cross section of the front portion.
9. The apparatus of claim 7 , wherein the center of the cross section of the protrusion is lower than the center of the cross section of the front portion.
10. The apparatus of claim 4 , wherein a cross section of the protrusion is elliptical.
11. The apparatus of claim 10 , wherein a center of the cross section of the protrusion is on a same axis as a center of a cross section of the front portion.
12. The apparatus of claim 10 , wherein a center of the cross section of the protrusion is not on a same axis as a center of a cross section of the front portion.
13. The apparatus of claim 12 , wherein the center of the cross section of the protrusion is higher than the center of the cross section of the front portion.
14. The apparatus of claim 12 , wherein the center of the cross section of the protrusion is lower than the center of the cross section of the front portion.
15. A cleaning probe used in an apparatus for cleaning a wafer using megasonic waves comprising:
a rear portion connected to a piezoelectric transducer configured to generate megasonic waves;
a front portion located opposite to the rear portion and located over the wafer; and,
a protrusion located between the rear portion and the front portion, and located at an edge portion of the wafer,
wherein a cross section width of the protrusion is larger than a cross section width of the front portion.
16. The cleaning probe of claim 15 , wherein the cleaning probe further comprises:
a front connection portion connecting the protrusion and the front portion, wherein a cross section width of the front connection portion varies over a length of the front connection portion; and,
a rear connection portion connecting the protrusion and the rear portion, wherein a cross section width of the rear connection portion varies over a length of the rear connection portion.
17. The cleaning probe of claim 16 , wherein a cross section of the protrusion is circular.
18. The cleaning probe of claim 17 , wherein a center of the cross section of the protrusion is on a same axis as a center of a cross section of the front portion.
19. The cleaning probe of claim 17 , wherein a center of the cross section of the protrusion is not on a same axis as a center of a cross section of the front portion.
20. The cleaning probe of claim 19 , wherein the center of the cross section of the protrusion is higher than the center of the cross section of the front portion.
21. The cleaning probe of claim 19 , wherein the center of the cross section of the protrusion is lower than the center of the cross section of the front portion.
22. The cleaning probe of claim 16 , wherein a cross section of the protrusion is elliptical.
23. The cleaning probe of claim 22 , wherein a center of the cross section of the protrusion is on a same axis as a center of a cross section of the front portion.
24. The cleaning probe of claim 22 , wherein a center of the cross section of the protrusion is not on a same axis as a center of a cross section of the front portion.
25. The cleaning probe of claim 24 , wherein the center of the cross section of the protrusion is higher than the center of the cross section of the front portion.
26. The cleaning probe of claim 24 , wherein the center of the cross section of the protrusion is lower than the center of the cross section of the front portion.