Understanding Film Thickness Measurements

Filmetrics measures a film's thickness by reflecting light off the film and analyzing the reflected light over a range of wavelengths. This technique is called spectral reflectance, and it has considerable advantages in speed, simplicity, and cost, especially over common techniques such as ellipsometry and profilometry.

To help our customers better understand spectral reflectance, Filmetrics has created an easy-to-understand guide that explains spectral reflectance and how it is used for thin-film measurements. This twelve-page guide is entitled "Taking the Mystery Out of Thin-Film Measurement" ("TMO" for short), and is useful for anyone in the thin-film industry. Whether your job is depositing, measuring, or using thin films, understanding the principles behind spectral reflectance will be a valuable addition to your knowledge base.

After a short introduction to thin-film technology, our TMO guide describes spectral reflectance for both single- and multiple-layer film stacks, as well the interactions of thickness measurements with optical constants. The last section compares the relative merits of spectral reflectance and ellipsometry.