Dressing apparatus for chemical mechanical polishing pad

A chemical mechanical polishing (CMP) dressing apparatus for conditioning and regenerating the working surface of a CMP polishing pad, comprising:

• a rotatable inner shaft defining a first axis;
• a non-rotating outer sleeve shaft disposed around the inner shaft;
• an air cap comprising a bottomless air chamber with at least one opening for receiving compressed air;
• an air cap support connected to the outer sleeve shaft and supporting the air cap;
• a carrier plate disposed beneath the air cap and having an upper surface, a lower surface, and a plurality of through holes communicating the upper surface and the lower surface, wherein the upper surface is coupled to the inner shaft so as to rotate the carrier plate about the first axis, and the through holes receive compressed air from the air cap when the rotation of the carrier plate brings them under the air cap;
• and
• a plurality of dressing tools, each having a mounting surface and a dressing surface, wherein the mounting surfaces of the dressing tools are mounted to the lower surface of the carrier plate with the dressing surfaces facing the working surface of the CMP pad;
• wherein, the rotation of carrier plate conditions and regenerates the working surface of the CMP pad by action of the dressing surfaces of the dressing tools, and compressed air provided through the air cap is forced through the plurality of through holes in the carrier plate to the working surface of the CMP pad, thereby sweeping off micro-particles and other types of contamination.