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NanoFab Tool: IPEC 472, Chemical Mechanical Polisher (CMP)

Chemical Mechanical Polisher (CMP)
Credit: NIST

Photo of the Chemical Mechanical Polisher

The CMP removes material both chemically, by use of a corrosive colloidal slurry, and mechanically, by way of a wafer carrier under controlled pressure rotating against a rotating polishing pad, with carrier and pad having nonconcentric axes of rotation. It is equipped with a primary platen to remove the material and a secondary platen to do the final polish and minimize the surface roughness. The system removes irregular topography and leaves wafers planar with sub-nanometer roughness.


  • Sample sizes: 100 mm, 150 mm and 200 mm in diameter wafers (pieces are not allowed)
  • Cassette-to-cassette capability for 100 mm wafers
  • Manual loading, one wafer at a time, for 150 mm and 200 mm wafers
  • Laterally oscillating wafer carrier 
  • In-situ pad conditioning on primary platen
  • Within wafer non-uniformity: typically, less than 3 % sigma/mean
  • Wafer-to-wafer non-uniformity: typically, less than 5 %
  • The removal rate is dependent on material, rotation speeds, pressure, type of slurry, concentration and slurry flow rate and can vary from a few nm/min to several hundred nm/min.

Usage Information

Operating Instructions


Typical Applications

  • Planarization of metal interconnects and vias: typically, Cu, W, Al, Au, Pt
  • Planarization of inter-layer dielectrics: typically, SiO2
  • General sample polishing to minimize surface roughness
Created April 10, 2019, Updated December 4, 2019