Method and device for the injection of CMP slurry
Disclosed is an apparatus for injecting slurry onto the polishing pad surface of a chemical mechanical polishing (CMP) tool. The disclosed apparatus includes a rectilinear shaped injector bottom, where multiple slots are created in the top surface of the injector bottom, allowing the injector bottom to flex and to conform to the polishing pad profile. CMP slurry or components thereof are introduced through one or more top surface openings, travel through the injector body, and exit through a slit or bottom surface opening. The slurry is spread into a thin film by the injector, and is introduced at the gap between the surface of the polishing pad and the wafer, along the leading edge of the wafer, in quantities small enough that all or most of the slurry is introduced between the wafer and the polishing pad.
1. An injector device for injecting slurry onto a polishing pad of a chemical mechanical polishing (CMP) tool, the injector device comprising:
an injector bottom, wherein the injector bottom comprises:
a top surface comprising one or more than one top surface opening;
a bottom surface comprising one or more than one bottom surface opening, wherein the one or more than one bottom surface opening is in fluid communication with the one or more than one top surface opening;
a leading edge, wherein the leading edge is chamfered;
a trailing edge;
and
a groove formed in the bottom surface, wherein the groove extends along a length of the injector bottom between the leading edge and the trailing edge, and wherein the groove comprises:
a leading sidewall, wherein the leading sidewall extends in a direction parallel to the leading edge;
and
a trailing sidewall, wherein the trailing sidewall extends in a direction parallel to the trailing edge;
wherein a CMP slurry introduced through the one or more than one top surface opening travels through the injector bottom and exits the injector device through the one or more than one bottom surface opening onto the polishing pad top surface;
wherein the bottom surface of the injector bottom further comprises a slit extending along the length of the injector bottom between the trailing sidewall and the trailing edge; and
wherein the top surface of the injector bottom further comprises a plurality of slots formed in the top surface, wherein the slots run from the leading edge to the trailing edge, and wherein a depth of each of the plurality of slots extends from the top surface of the injector bottom into the injector bottom, and wherein the depth of each of the plurality of slots does not extend all the way to the bottom surface.
2. The injector device of claim 1 , wherein the injector bottom is rectilinear shaped.
3. The injector device of claim 2 , wherein the bottom surface rests on the polishing pad.
4. An injector device for injecting slurry onto a polishing pad of a chemical mechanical polishing (CMP) tool, the injector device comprising:
a rectilinear shaped injector bottom, wherein the injector bottom comprises:
a top surface comprising one or more than one top surface opening;
a bottom surface comprising one or more than one slit, wherein the one or more than one slit is in fluid communication with the one or more than one top surface opening;
a leading edge;
and
a trailing edge; and
a first set of weights positioned on top of the top surface;
wherein a CMP slurry introduced through the one or more than one top surface opening travels through the injector bottom and exits the injector device through the one or more than one slit onto the polishing pad top surface.
5. The injector device of claim 4 , wherein the bottom surface rests on a top surface of the polishing pad.
6. The injector device of claim 4 , wherein the injector device has a center of gravity between the leading edge and the trailing edge, and wherein the distance from the leading edge to the center of gravity is larger than the distance from the center of gravity to the trailing edge.
7. The injector device of claim 4 , further comprising a second set of weights positioned on top of the first set of weights.
8. The injector device of claim 4 , wherein the top surface of the injector bottom further comprises one or more than one slot formed in the top surface, wherein the one or more than one slot runs from the leading edge to the trailing edge, wherein a depth of each of the one or more than one slot extends into the injector bottom from the top surface, and wherein the depth of each of the one or more than one slot does not extend all the way to the bottom surface.
9. The injector device of claim 4 , further comprising a groove formed in the bottom surface running along a length of the injector device, wherein the groove is located between the leading edge and the trailing edge.
10. An injector device for injecting slurry onto a polishing pad of a chemical mechanical polishing (CMP) tool, the injector device comprising:
a rectilinear shaped injector bottom, wherein the injector bottom comprises:
a top surface comprising one or more than one top surface opening;
a bottom surface comprising one or more than one bottom surface opening, wherein the one or more than one bottom surface opening is in fluid communication with the one or more than one top surface opening;
a leading edge;
a trailing edge;
and
one or more than one slot formed in the top surface, wherein a depth of each of the one or more than one slots extends from the top surface into the injector bottom, and wherein the depth of each of the one or more than one slots does not extend to the bottom surface;
wherein a CMP slurry introduced through the one or more than one top surface opening travels through the injector bottom and exits the injector device through the one or more than one bottom surface opening onto the polishing pad top surface.
11. The injector device of claim 10 , wherein the bottom surface rests on a top surface of the polishing pad.
12. The injector device of claim 10 , wherein the one or more than one bottom surface opening forms a slit in the bottom surface.
13. The injector device of claim 12 , wherein the slit runs parallel to the injector trailing edge.
14. The injector device of claim 10 , wherein the leading edge is straight, and wherein the trailing edge is straight.
15. The injector device of claim 10 , further comprising a groove formed in the bottom surface running along the length of the injector bottom, wherein the groove is located between the leading edge and the trailing edge.