Polishing liquids for activating and/or conditioning fixed abrasive polishing pads, and associated systems and methods
Polishing liquids for activating and/or conditioning fixed abrasive polishing pads, and associated systems and methods are disclosed. A method in accordance with one embodiment of the invention includes disposing a polishing liquid on a polishing surface of a microfeature workpiece polishing pad. The polishing pad can include a matrix material and a plurality of abrasive elements fixedly distributed in the matrix material. The polishing liquid can include a plurality of particles that are at least approximately chemically inert with respect to the abrasive elements. In a particular embodiment, the particles can have a polymeric, non-ceramic composition. The method can further include moving at least one of the polishing pad and the plurality of particles relative to the other to remove deposits from the polishing pad. This operation can be performed serially or simultaneously with using the polishing pad to remove material from a microfeature workpiece.
1. A method for using a polishing pad, comprising:
disposing a polishing liquid on a polishing surface of a polishing pad, the polishing pad including a matrix material and a plurality of abrasive elements fixedly distributed in the matrix material, the polishing liquid including a plurality of particles that are suspended in the polishing liquid and at least approximately chemically inert with respect to the abrasive elements;
contacting the polishing surface of the polishing pad with a semiconductor wafer in the presence of the polishing liquid to remove material from the semiconductor wafer, at least a part of the removed material forming deposits on the abrasive elements of the polishing pad; and
moving at least one of the polishing pad and the plurality of particles relative to the other to remove the deposits from the abrasive elements of the polishing pad.
2. The method of claim 1 wherein disposing a polishing liquid includes disposing a polishing liquid having a plurality of particles with a polymeric, non-ceramic composition, a generally spherical shape, an average diameter in the range of from about 20 nanometers to about five hundred microns, and a concentration in the polishing liquid of from about 20 ppm to about 5%, and wherein the method further comprises:
moving at least one of the polishing pad and the semiconductor wafer relative to the other to remove material from the semiconductor wafer simultaneously with removing deposits from the polishing pad.
3. The method of claim 1 , wherein disposing a polishing liquid includes disposing a polishing liquid having particles with a polymeric, non-ceramic composition.
4. The method of claim 1 wherein moving at least one of the polishing pad and the plurality of particles includes moving at least one of the polishing pad and the plurality of particles relative to the other to remove the deposits from the abrasive elements of the polishing pad without reducing a uniformity of the polishing surface.
5. The method of claim 1 , further comprising placing a generally rigid member that does not include a microelectronic workpiece in contact with the polishing pad and the polishing liquid, and wherein removing deposits from the polishing pad includes moving at least one of the polishing pad and the generally rigid member relative to the other.
6. The method of claim 1 wherein disposing a polishing liquid includes disposing a polishing liquid having a plurality of particles with generally spherical shapes.
7. The method of claim 1 wherein disposing a polishing liquid includes disposing a polishing liquid having a plurality of particles with an average diameter in the range of from about 20 nanometers to about five hundred microns.
8. The method of claim 1 wherein disposing a polishing liquid includes disposing a polishing liquid having a plurality of particles with an average hardness that is less than a hardness of the abrasive elements.
9. The method of claim 1 wherein disposing a polishing liquid includes disposing a polishing liquid having a plurality of particles with an average size at least approximately the same as an average size of the abrasive elements.
10. The method of claim 1 wherein the polishing pad includes a plurality of projections and wherein the abrasive elements are housed in the projections, further wherein disposing a polishing liquid includes disposing a polishing liquid having a plurality of particles that are smaller than the projections.
11. The method of claim 1 wherein disposing a polishing liquid includes disposing a polishing liquid having a concentration of particles in the range of from about 20 ppm to about 5%.
12. The method of claim 1 wherein removing deposits from the polishing pad includes removing deposits without engaging an end effector with the polishing pad and without engaging a brush with the polishing pad.
13. The method of claim 1 wherein the polishing liquid is a first polishing liquid and wherein the method further comprises:
removing the first polishing liquid from the polishing pad;
disposing a second polishing liquid on the polishing pad, the second polishing liquid having a composition different than a composition of the first polishing liquid;
placing a semiconductor wafer in contact with the polishing pad and the second polishing liquid; and
moving at least one of the polishing pad and the semiconductor wafer relative to the other to remove material from the semiconductor wafer.
14. A method for removing material from a semiconductor wafer, comprising:
disposing a polishing liquid on a polishing surface of a polishing pad, the polishing pad including a matrix material and a plurality of abrasive elements fixedly distributed in the matrix material, the polishing liquid including a plurality of particles that are at least approximately chemically inert with respect to the abrasive elements;
contacting a semiconductor wafer with the polishing pad to remove material from the semiconductor wafer;
depositing the removed material onto the abrasive elements of the polishing pad; and
moving at least one of the polishing pad and the semiconductor wafer relative to the other to remove material from the semiconductor wafer while simultaneously removing the deposited material from the abrasive elements of the polishing pad.
15. The method of claim 14 wherein disposing a polishing liquid includes disposing a polishing liquid having a plurality of particles with a polymeric, non-ceramic composition, a generally spherical shape, an average diameter in the range of from about 20 nanometers to about five hundred microns, and a concentration in the polishing liquid of from about 20 ppm to about 5%.
16. The method of claim 14 wherein disposing a polishing liquid includes disposing a polishing liquid having a plurality of particles with a polymeric, non-ceramic composition.
17. The method of claim 14 wherein disposing a polishing liquid includes disposing a polishing liquid having a plurality of particles with generally spherical shapes.
18. The method of claim 14 wherein disposing a polishing liquid includes disposing a polishing liquid having a plurality of particles with an average diameter in the range of from about 20 nanometers to about five hundred microns.
19. The method of claim 14 wherein disposing a polishing liquid includes disposing a polishing liquid having a plurality of particles with an average hardness that is less than a hardness of the abrasive elements.
20. The method of claim 14 wherein disposing a polishing liquid includes disposing a polishing liquid having a plurality of particles with an average size at least approximately the same as an average size of the abrasive elements.
21. A method for removing material from a semiconductor wafer, comprising:
supporting a semiconductor wafer relative to a polishing pad, the polishing pad including a matrix material and a plurality of abrasive elements fixedly distributed in the matrix material;
disposing a polishing liquid on the polishing surface of the polishing pad, the polishing liquid including a plurality of particles that are at least approximately chemically inert with respect to the abrasive elements, wherein at least one of a size and a hardness of the particles is different than that of the abrasive elements of the polishing pad;
contacting the abrasive elements of the polishing pad with the semiconductor wafer to remove material from a surface of the semiconductor wafer;
depositing the removed material from the semiconductor wafer on the abrasive elements of the polishing pad; and
scrubbing the abrasive elements with the particles in the polishing liquid to remove the deposited material from the abrasive elements of the polishing pad.
22. The method of claim 21 , further comprising increasing a rate of removing the deposited material from the abrasive elements by increasing a concentration of the particles in the polishing liquid.
23. The method of claim 21 wherein disposing a polishing liquid includes disposing the polishing liquid on the polishing surface of the polishing pad before contacting the abrasive elements of the polishing pad with the semiconductor wafer.