LayTec’s spectral reflectometer EpiR DA UV has proven to be an ideal tool for direct in-situ monitoring of thin-film optical properties on the substrate itself. Since it is a non-destructive optical method, the sensor obtains information right from the individual layers of the OLED structure inside the in-line evaporation system.

The monitoring system has been successfully tested at Fraunhofer Institute for Photonic Microsystems in Dresden (Germany).  It was attached to a quartz optical view port at the transfer chamber. After each deposition step the substrate was moved to the measurement position and a full reflectance spectrum was taken. Such sprectra are called “single-shot” spectra because they are not taken continuously during the deposition but as separate spectra individually just after the respective deposition steps.

For further details see the EpiR datasheets and related application notes.