Imaging Spectroscopic Reflectometry is used for investigating high spatial resolution of small (typically 50x50 µm to 500x500 µm) areas. As a consequence, the two main applications are half-tone process control (where photoresist thickness characterization is possible down to 1 µm channel width) and printed OLED thickness map. By means of a high-brightness Xe-lamp as light source and high-precision monochromator fast and accurate measurement can be performed. The wavelength resolution is adjustable down to several nanometers and wavelength range can be chosen according to the thickness and optical properties of the measured layer.

The wide wavelength-range light source is filtered by a monochromator. The monochrome light reaches the sample and a 2D image is captured in the same time. This process is repeated for every selected wavelength which will result in a set of images, each represent the result at a given wavelength. Using these pictures the software calculates the reflectance spectra for each selected site.

Imaging Spectroscopic Ellipsometry requires very precise focusing which is done by a built-in focusing system utilizing a fast and precise piezoelectric motor.