Chemical mechanical planarization apparatus and method

Abstract

A polishing apparatus, specifically for performing chemical mechanical planarization on an object such as a substrate, which may be a semiconductor wafer. The polishing apparatus may include a rotatable polishing pad having an axial center of rotation and a slurry delivery conduit configured to introduce polishing slurry through said axial center of rotation. The polishing slurry may be configured to be dispensed directly beneath the rotatable polishing pad to enable localized polishing of a surface of a substrate located below or beneath the rotatable polishing pad.

What is claimed is: 
     
         1 . A polishing apparatus comprising:
 a rotatable polishing pad having an axial center of rotation;   a slurry delivery conduit configured to introduce polishing slurry through said axial center of rotation; and   wherein the polishing slurry is configured to be dispensed directly beneath the rotatable polishing pad to enable localized polishing of a surface of a substrate.   
     
     
         2 . The apparatus of  claim 1 , wherein the rotatable polishing pad has a diameter less than 50 mm to enable high-resolution planarization of localized substrate regions of the substrate surface. 
     
     
         3 . The apparatus of  claim 1 , wherein the slurry delivery conduit is at least partially integrated within a rotary union to maintain continuous flow of the polishing slurry during rotation of the rotatable polishing pad about the axial center of rotation. 
     
     
         4 . The apparatus of  claim 1 , wherein the polishing slurry is configured to be dispensed from an outlet of the slurry delivery conduit at a controlled flow rate that is synchronized with a rotational speed of the rotatable polishing pad to optimize material removal rate and uniformity. 
     
     
         5 . The apparatus of  claim 1 , wherein the substrate comprises silicon carbide (SiC), germanium (Ge), or other advanced semiconductor materials requiring localized planarization. 
     
     
         6 . The apparatus of  claim 1 , wherein the a pressure applied by the rotatable polishing pad is controlled by an upward loading of the substrate being polished. 
     
     
         7 . A substrate polishing system comprising:
 a support member;   a substrate supported by the support member, the substrate having a first surface;   a polishing assembly comprising a polishing arm that extends over the substrate and a polishing pad coupled to an end of the polishing arm, the polishing pad comprising a top side and a bottom side opposite the top side, the polishing pad being configured to rotate about a rotational axis;   a slurry delivery conduit extending through the polishing pad from the top side to the bottom side, the slurry delivery conduit terminating in an outlet opening in the bottom side of the polishing pad;   a source of a polishing slurry fluidly coupled to the slurry delivery device, the polishing slurry configured to be introduced into the slurry delivery conduit and dispensed from the outlet opening in the bottom side of the polishing pad onto the first surface of the substrate during a polishing process while the polishing pad rotates about the rotational axis.   
     
     
         8 . The substrate polishing system according to  claim 7  wherein the polishing pad has a first diameter and the substrate has a second diameter that is greater than the first diameter.