Abstract: The present invention includes a platen having a plurality of concentric fluid-tight plenums for receiving fluids. One or more fluid delivery systems may be used to control the flow rate and composition of fluids communicated to the plenums. The top surface of the platen may have holes for allowing the fluids, once inside the plenums, to travel to the top surface of a polishing pad. By controlling the flow rate and composition of fluids, the material removal rate on the front surface of the wafer may also be controlled. The polishing pad is preferably orbited during the planarization process. A metrology instrument may be used for measuring the front surface of the wafer. Data regarding the measurements may be used by a computer to determine if different flow rates and/or composition of fluids should be used to compensate for nonuniform polishing of the wafer.
Abstract: A multi-step CMP system is used to polish a wafer to form metal interconnects in a dielectric layer upon which barrier and metal layers have been formed. A first polish removes an upper portion of the metal layer using a first slurry and a first set of polishing parameters, leaving residual metal within the dielectric layer to serve as the metal interconnects. A second polish of the wafer on the same platen and polishing pad removes portions of the barrier layer using a second slurry under a second set of polishing parameters. The second polish clears the barrier layer from the upper surface of the dielectric layer, thereby forming the metal interconnect. To reduce dishing and dielectric erosion, the second slurry is selected so that the barrier layer is removed at a faster rate than the residual metal within the dielectric layer. A cleaning step may be optionally performed between the first and second polishes.
Type:
Grant
Filed:
December 16, 1998
Date of Patent:
July 17, 2001
Assignee:
SpeedFam-IPEC
Inventors:
Karey Holland, Ajoy Zutshi, Fen Dai, Yehiel Gotkis, C. Jerry Yang, Dennis Schey, Fred Mitchel, Lin Yang
Abstract: A carrier for semiconductor wafers to be polished comprises a backing pad vulcanized to a pressure plate. The backing pad is formed of a rubber material such as neoprene, SBR or natural rubber. An adhesive film of a thermosetting, thermally reactive material forms an integral bond between the backing pad and pressure plate. The backing pad, adhesive film and pressure plate together comprise a nearly ideally elastic assembly. The exposed face of the backing pad is profiled to a desired profile without effecting crumbling of the rubber material.
Type:
Grant
Filed:
March 26, 1999
Date of Patent:
August 1, 2000
Assignee:
Speedfam-IPEC
Inventors:
Clinton O. Fruitman, Thomas K. Crosby, James Schlueter