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Refractive Index and Extinction Coefficient Analyzer

Photo of a piece of equipment that looks similar to a copy machine, but with an additional small vertical rectangular frame on top, and a smaller white box on top of that frame.  Several large buttons are located on the front of the base unit.

Refractive index (n) and extinction coefficient (k) analyzer that is one of the Stand-alone Measurements and Characterization tools in the Process Development and Integration Laboratory.

This page provides details on the refractive index (n) and extinction coefficient (k) analyzer—or n&k analyzer—in the silicon area of the Process Development and Integration Laboratory. This capability should be operational within 2009.

This system simultaneously determines thickness and n and k in the spectral range of 190 to 1000 nm. It provides non-destructive, real-time, high-throughput measurements directly on the device and collects reflectance and transmission data at the same point.


  • Determining n and k values
  • Collecting reflectance (R) and transmission (T) data

Special features:

  • Operates in the spectral range of 190 to 1000 nm
  • Non-destructive, real-time, high-throughput measurements
  • Uses advanced pattern-recognition software
  • Spot size: R = 50 μm, T < 400 μm
  • Can map thickness and optical properties on large (157 mm x 157 mm) substrates

Contact Qi Wang for more details.