METHOD AND APPARATUS FOR CHEMICAL-MECHANICAL PLANARIZATION
A method and apparatus for performing chemical-mechanical planarization (CMP) is disclosed, which in one embodiment includes a CMP tool for polishing a semiconductor wafer. The CMP tool includes a slurry mixture that has slurry beads. The slurry beads are formed of a polymer material. The slurry beads are used to remove summits and non-uniformities on the semiconductor wafer. In some embodiments the CMP tool includes a counter-face that replaces the polishing pad of a conventional CMP tool. In some embodiments the counter-face is made of polycarbonate. In another embodiment a slurry mixture for use with a CMP tool is disclosed. The slurry mixture includes slurry beads, where each of the slurry beads has a diameter of between 0.1 and 1000 microns, or in some embodiments a diameter of between 10 and 50 microns.
1 . A slurry mixture for use with a chemical-mechanical planarization (CMP) tool, the slurry mixture comprising slurry beads, wherein the slurry beads comprise a polymer material.
2 . The slurry mixture of claim 1 , wherein the slurry beads each have a diameter of between 0.1 and 1000 microns.
3 . The slurry mixture of claim 1 , wherein the slurry beads each have a diameter of between 10 and 50 microns.
4 . The slurry mixture of claim 1 , wherein the slurry beads comprise polyurethane.
5 . The slurry mixture of claim 1 , wherein the slurry beads comprise between 0.001 and 30 weight percent of the slurry.
6 . The slurry mixture of claim 1 , wherein the slurry beads comprise between 5 and 20 weight percent of the slurry.
7 . A chemical-mechanical planarization (CMP) tool for polishing a semiconductor wafer, wherein the CMP tool comprises:
a slurry mixture comprising slurry beads, wherein the slurry beads each have a diameter of between 0.1 and 1000 microns; and
a counter-face, wherein the counter-face holds the slurry beads against the semiconductor wafer.
8 . The tool of claim 7 , wherein the slurry beads are formed of a man-made polymer material.
9 . The tool of claim 7 , wherein the slurry beads each have a diameter of between 1 and 100 microns.
10 . The tool of claim 7 , wherein the counter-face is formed of polycarbonate.
11 . The tool of claim 7 , wherein the counter-face is formed of quartz.
12 . The tool of claim 7 , wherein the slurry beads comprise a slurry bead static or surface charge with a polarity opposite to a polarity of a counter-face static or surface charge of the counter-face.
13 . The tool of claim 7 , wherein the slurry beads each have a diameter approximately equal to the distance between the counter-face and the semiconductor wafer.
14 . A method of polishing a semiconductor wafer using a chemical-mechanical planarization (CMP) tool, the method comprising the step of polishing the semiconductor wafer using a slurry mixture, wherein the slurry mixture comprises slurry beads, and wherein the slurry beads each have a diameter of between 0.1 and 1000 microns.
15 . The method of claim 14 , wherein the CMP tool comprises a counter-face formed of polycarbonate.
16 . The method of claim 15 , further comprising the step of treating the counter-face such that an attractive force is generated between the counter-face and the slurry beads.
17 . The method of claim 15 , wherein the slurry beads each have a diameter approximately equal to the distance between the counter-face and the semiconductor wafer.
18 . The method of claim 14 , wherein the slurry beads each have a diameter of between 10 and 50 microns.
19 . The method of claim 14 , wherein the slurry beads comprise between 0.001 and 30 weight percent of the slurry mixture.
20 . The method of claim 14 , further comprising the steps of:
removing a polishing pad from the CMP tool;
and
installing a counter-face in place of the polishing pad.