The EP4, our latest generation of imaging ellipsometers, combines ellipsometry and microscopy. This enables the characterization of thickness and refractive index with the sensitivity of ellipsometry on micro-structures as small as 1 µm. The microscopic part enables a simultaneous measurement of all structures inside the field of view of the optical system. Conventional ellipsometers have to focus on the measurement spot, while not achieving comparable lateral resolution, and measure spot by spot.
The microscopic part of the EP4 enables an ellipsometric-enhanced contrast for microscopic images obtained. Minor changes in refractive index or thickness can be seen in the live view of the camera. This allows to identify regions of interest for the ellipsometric measurements to obtain values for thickness (0.1 nm - 10 µm) and refractive index. 3D maps of the lateral variation of thickness and/or refractive index can be recorded within a single measurement.
Combination with complementary methods, e.g. AFM, QCM-D, reflectometry, Raman, is available to allow the observation of the same area.
Further accessories may expand measurement possibilities under controlled ambient conditions or temperature changes.