Thin film (ITO, OLED, LTPS, IGZO, SiNx, SiOx, photoresist, etc.) thickness and optical properties is one of the key process control parameters. Using Spectroscopic Ellipsometer of Semilab fast (measurement speed is similar to reflectometers) and accurate measurement can be performed at any size of the panel.

Using our advanced analysis software, the following parameters can be determined as well: optical band gap energy, transmission, roughness, crystallinity related parameter (in case of LTPS).

SiOx/Glass structure can be a challenge to measure using conventional optical metrologies, however due to the principle of ellipsometer used in FPT even such low contrast structures can be measured accurately.




In the semiconductor industry, there is continuous demand for higher performance and denser integrated circuits. These requirements push the advancement of technology which requires solving of manufacturing challenges. A key to success is to understand the chemical, mechanical and physical properties of wide range of materials used in a typical integrated circuit.

The µSE tool is designed to measure thin film thickness and optical properties inside a <50µm test pad on semiconductor product wafers. The applied measurement technique for obtaining these parameters in a high accuracy and repeatable way is spectroscopic ellipsometry. The μSE tool uses optimized spectroscopic ellipsometer (SE) arms and optics for the measurement inside small boxes of patterned Si wafers.

Ellipsometry measures the phase of the reflected light from the sample, therefore it is relatively insensitive for intensity fluctuations. The raw measurement data represent the complex information from the layer stack which then need to be modeled optically. The measurement results are obtained through numerical regression process of the model data to the raw measurement spectrum.




  • Non-destructive optical technique, based on measurement of the change of the polarisation state of light after reflection at non normal incidence on the surface to study.
  • It is a higly sensitive even for layer thickness below 5 nm
  • Extremely versatile technique: it gives acccess to numerous parameters which characterize multilayer structures (eg. layer thickness, refractive index, absorption, porosity).

Product Line


Refractive optical design in compact realization: short optical path inside the measurement arms (reduced alignment artifact errors). Active temperature control: stabilized environment for system reli-ability enhancement. Uniqe patented high brightness light source for outstanding SNR. CCD detector array (spectrum is taken simultaneously at different wavelengths).




FPT can be equipped with:

Optical thickness and refractive index of multilayered oxide and semiconductor structures can be determined by spectroscopic ellipsometery at different process steps. The quality of the ELA process can also be monitored by measuring crystallinity, u-PCR and line mura density. Contact angle, stress and resistivity measurements are also available.

The hardware and software are fully controlled by SEMILAB from the design to the integrated software communication with the fab.

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