Regress Pro is scientific / industrial software that can be used to study experimental data coming from spectroscopic ellipsometers or reflectometers.

The application lets you load spectroscopic data coming from an ellipsometer or reflectometer and analyze them using well-proven algorithms to determine various physical parameters like film's thickness or refractive index.

Regress Pro lets you define a model of the film stack using a simple declarative language. You can also define a fit algorithm to analyze the data or, in alternative, perform an interactive fit of the data.

Several models are available to define the dispersion curves of the materials and in addition some of the most common materials are provided in the library.

The application has been developed mainly looking to the application of thin film measurement in semiconductor industry.


Here a couple of screenshots of Regress Pro at work:

Regress Pro
Interactive fit of ellipsometric data if visible and UV range.

In the following screenshot we show the dispersion optimizer at work.

Dispersion Fit at work
Fit of cr-Si dispersion curve with a simple HO model.


The latest release of the application is Regress Pro 1.4.

While Regress Pro is free software and is published under the GNU GPL license a registration is required for the precompiled binaries.


2011-08-27 Regress Pro 1.4.1 has been released
This release fixes several bugs and improve some small usability issues. This is a recommended upgrade for all the users of Regress Pro.
2011-08-01 Regress Pro 1.4 has been released
This release has several major new features:
  • Interactive fit of spectra is now available.
  • Interactive Dispersion model optimizer also implemented.
  • A library of standard dispersion model is available.
In addition this new release introduce a new better graphical engine based on the excellent AGG library. It does also fix some bugs and improve some usability aspect and the user's manual has been updated.
2009-11-03 Regress Pro 1.3.2 has been released
This release introduce the simultaneous fit of multiple spectra