Patent ID: 8460507

Claim:
An apparatus for use in chemical-mechanical polishing (CMP) process comprising a movable platen adapted to hold a polishing pad on the platen; a movable polishing head adapted to hold a substrate and to urge a surface of the substrate against the polishing pad at a selected down force; a CMP slurry conveyance system adapted to deposit a CMP slurry onto a surface of the pad and thereby to contact the CMP slurry with the surface of the substrate; and a CMP slurry withdrawal port on or in close proximity to a polishing head, the withdrawal port being in fluid-flow relation with a sampling line, the withdrawal port and sampling line together being adapted to remove a portion of the CMP slurry from the surface of the polishing pad, thus forming a used CMP slurry line; wherein, during use, the platen and polishing head are disposed in an opposed, parallel relation to one another with the pad and substrate therebetween; the platen and the polishing head moving relative one another to provide a frictional force between the polishing pad and the surface of the substrate being urged against the pad to abrade and polish the surface of the substrate, and the sampling line providing a stream of used slurry for determination of a physical or chemical characteristic thereof, and wherein the sampling line includes an in-line used-slurry characteristic sensor adapted to measure a physical or chemical characteristic of the used slurry that is withdrawn from the surface of the pad and to transmit a first output signal related to the physical or chemical characteristic to a first data receiving device during the course of polishing the substrate, and wherein the CMP slurry conveyance system includes an in-line fresh-slurry characteristic sensor adapted to measure a physical or chemical characteristic of the CMP slurry prior to depositing the CMP slurry onto the polishing pad, and to transmit a second output signal related to the physical or chemical characteristic of the CMP slurry to a second data receiving device during the course of polishing the substrate.