Method for removing contamination from a chuck surface
A method for decontaminating support surfaces of a wafer chuck, such as a wafer chuck, entails lightly passing a treatment tool having a nominally flat contacting surface over the regions of the chuck where contaminants are to be removed. The treatment tool and the chuck surface may have about the same hardness. The treatment tool may be minimally constrained so that it may conform to the surface being processed. When the treatment tool is contacted to a flat surface, the locust of contact may be in the form of a circle, ring or annulus. At higher application pressures, the treatment tool will abrade the chuck, which here is to be avoided, or at least minimized. Thus, the instant inventors have discovered that the same treatment tool that is used to engineer the elevation or profile of the surface, and its roughness, at lower application pressures can be used to remove grinding debris and other contaminants from the surface.
1. A method for removing contamination from a the support surface of a chuck, comprising:
(a) providing a treatment tool having a treatment surface configured to contact and pass lightly over said support surface, said treatment surface having a slight toroidal shape;
(b) moving said treatment tool over at least a portion of said support surface containing contamination, wherein at least during said moving, the force applied by said treatment tool against said support surface is maintained at a level of pressure sufficiently low such that said treatment surface does as to not abrade said support surface; and
(c) continuing said moving for a time or a number of passes over the contaminated surface sufficient to remove said contamination, and (d) wherein a diameter of said support surface is greater than a the size of said treatment surface.
2. The method of claim 1 , wherein said treatment tool is minimally constrained, thereby permitting said treatment surface to conform to the support surface of said wafer chuck.
3. The method of claim 1 , wherein said surface of said treatment tool is shaped as a toroid.
4. The method of claim 1 , wherein said treatment tool comprises reaction bonded SiC.
5. The method of claim 1 , wherein said surface of said treatment tool and said support surface of said chuck have about the same hardness.
6. The method of claim 1 , wherein said treatment tool has a small cross-section, thereby enabling said treatment tool to process areas on said chuck that are recessed relative to said support surface of said chuck.
7. A method for removing contamination from a the support surface of a chuck, comprising:
(a) providing a treatment tool having a surface configured to make contact with, and pass over, said support surface, said treatment tool surface shaped such that minimally constrained contact of said treatment tool surface to a flat surface, is in the form of a circle;
(b) moving said treatment tool surface over at least a portion of said chuck support surface containing contamination, wherein at least during said moving, the force applied by said treatment tool surface against said support surface is maintained at a level of pressure sufficiently low such that said treatment tool surface does not damage a flatness of said chuck support surface;
(c) continuing said moving for a time or a number of passes over the contaminated surface sufficient to remove said contamination, (d) wherein a diameter of said support surface is greater than a size of said treatment tool surface; and
(e) further wherein said treatment tool surface and said support surface of said chuck have about the same hardness.
8. The method of claim 7 , wherein said treatment tool is held in such a manner that the pressure applied minimizes erosion of said chuck and tool.
9. A method for removing contamination from a the support surface of a chuck, comprising:
(a) providing a treatment tool having a surface configured to contact and pass over said support surface, said treatment tool surface configured such that a conforming contact of said treatment tool surface and a flat surface is a circle;
(b) moving said treatment tool over at least a portion of said support surface containing contamination, wherein at least during said moving, the force applied by said treatment tool against said support surface is maintained at a level of pressure sufficiently low so as to not alter a flatness or roughness of said support surface;
(c) continuing said moving for a time or a number of passes over the contaminated surface sufficient to remove said contamination, (d) wherein a diameter of said support surface is greater than a size of said treatment tool surface; and
(e) further wherein said treatment tool has a hardness that is at least as high as that of said support surface, thereby avoiding changing a texture of said support surface .
10. The method of claim 9 , wherein said treatment tool comprises SiC.