Spectroscopic Ellipsometer

SE Series - Angstrom Sun Technologies, Inc. (AST)

Spectroscopic Ellipsometer SE series are advanced models built by Angstrom Sun Technologies Inc. Ellipsometry is a technique utilizing polarization state changes after light beam reacts with probing samples. A typical ellipsometer setup includes a light source, polarizing optics (like polarizer, analyzer, phase retarder or called as compensator), sample stage, detecting unit, incident angle change mechanism, computer and software for data acquisition and modeling. Not like reflectometer, ellipsometer parameters (Psi and Del) are always obtained at non normal incident angles. By varying incident angle. many more data sets can be obtained which will be helpful in refining model, reducing uncertainty and improving user's confidence on model's output. Therefore, variable angle ellipsometer is far more powerful than fixed angle ellipsometers. Furthermore, by utilizing broadband light source, spectroscopic data over a wavelength range with many wavelength points can be obtained and thus measurement precision and accuracy for optical properties can be greatly improved. The measurement speed for spectroscopic data has been overcome by implementing an advanced detector array so thousands of data can be acquired simultaneously. With such configuration and capable of collecting more data sets, the complicated layer stacks could be analyzed with powerful functions built within software.