Share Email Print

Proceedings Paper

Measuring Step Heights Using An Optical Profiler
Author(s): Katherine Creath
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Two-wavelength phase-shifting interferometry is applied to an interference phase-measuring microscope enabling the measurement of step heights. The surface is effectively tested at a synthesized equivalent wavelength λeq = λaλb/|λa - λb| using measurements made at wavelengths λa and λb. The rms repeatabilty of the technique is λ/1000 at the equivalent wavelength. To improve the precision of the data, the phase ambiguities in the single wavelength data are removed using the equivalent wavelength results to determine fringe orders. When this correction is made, a measurement dynamic range (feature height/rms repeatability) of 104 is obtainable. This technique enables features of up to 10 μm in height to be measured with a 10x objective.

Paper Details

Date Published: 25 November 1986
PDF: 6 pages
Proc. SPIE 0661, Optical Testing and Metrology, (25 November 1986); doi: 10.1117/12.938629
Show Author Affiliations
Katherine Creath, WYKO Corporation (United States)

Published in SPIE Proceedings Vol. 0661:
Optical Testing and Metrology
Chander Prakash Grover, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?