Method and device for the injection of CMP slurry
In a certain embodiment, the invention comprises an apparatus for injecting slurry between the wafer and the pad in chemical mechanical polishing of semiconductor wafers comprising an injector the leading edge of which possess bays, depressions or notches that capture spent slurry and hold it long enough for it to transfer heat from the polishing reaction to the pad or through the injector to the new slurry before the said spent slurry is thrown from the polishing pad. The effect is to considerably improve the removal rate, reduce slurry consumption and reduce operating time.
1. A device for injecting slurry between a wafer and a pad in chemical mechanical polishing of semiconductor wafers comprising an injector, the bottom surface of the leading edge of which possesses one or more bays, depressions or notches wherein the one or more bays, depressions, or notches are separated from a slurry inlet structure by a contact distance.
2. A device for injecting slurry according to claim 1 wherein number of bays, depressions or notches is five or more.
3. A device for injecting slurry according to claim 2 wherein the number of bays depressions or notches is 10 or more.
4. A device for injecting slurry according to claim 1 wherein the bays, depressions or notches are all the same shape.
5. A device for injecting slurry according to claim 1 wherein the bays, depressions or notches are all the same size.
6. A device for injecting slurry according to claim 1 wherein the bays, depressions or notches are all progressively larger along the leading edge.
7. A device for injecting slurry according to claim 1 wherein the shape of the bays, depressions or notches is a channel with perpendicular walls ending in a semicircle.
8. A device for injecting slurry according to claim 7 wherein the orientation of the lengthwise axis of the bays, depressions or notches is parallel to the direction of motion of the polishing pad at the point of contact with the leading edge of the injector traversed by the said axis.
9. A method for injecting slurry between a wafer and a pad in chemical mechanical polishing of semiconductor wafers using an injector wherein the bottom surface of the leading edge of which possesses one or more bays, depressions or notches wherein the one or more bays, depressions, or notches are separated from a slurry inlet structure by a contact distance.
10. A method for injecting slurry according to claim 9 wherein number of bays, depressions or notches of the injector is five or more.
11. A method for injecting slurry according to claim 10 wherein the number of bays depressions or notches of the injector is 10 or more.
12. A method for injecting slurry according to claim 9 wherein the bays, depressions or notches of the injector are all the same shape.
13. A method for injecting slurry according to claim 9 wherein the bays, depressions or notches of the injector are all the same size.
14. A method for injecting slurry according to claim 9 wherein the bays, depressions or notches of the injector are all progressively larger along the leading edge.
15. A method for injecting slurry according to claim 9 wherein the shape of the bays, depressions or notches of the injector is a channel with perpendicular walls ending in a semicircle.
16. A method for injecting slurry according to claim 15 wherein the orientation of the lengthwise axis of the bays, depressions or notches of the injector is parallel to the direction of motion of the polishing pad at the point of contact with the leading edge of the injector traversed by the said axis.
17. A device for injecting slurry according to claim 1 wherein the injection is not done through slurry inlets, channels or chambers or slits or holes in the bottom surface of the device.
18. A method for injecting slurry according to claim 9 wherein the injection is not done through slurry inlets, channels or chambers or slits or holes in the bottom surface of the device.