In collaboration with Fraunhofer Institute for Photonic Microsystems (IPMS) in Dresden, Germany, LayTec has adopted its spectral reflectometer EpiR DA to an OLED in-line evaporation system to monitor UV-VIS reflectivity spectra of individual layers during production process.
Michael Eritt, member of the group “Technologie-Module und Anlagentechnik” headed by Christian May at IPMS, uses the sensor for direct monitoring of thin-film optical properties on glas and foil substrates inside the in-line evaporation system. After each deposition step the substrate is moved to the measurement position and the sensor takes a full reflectance spectrum. The spectra allow calculating an accurate thickness of each individual layer by using special multi-layer analysis algorithms.
According to Mr. Eritt, “The advantage of in-situ monitoring is terrific. In case of ex-situ measurements the very sensitive organic layers are exposed to oxygen and moisture. In-situ monitoring enables reproducible detection of layer reflectance without taking them out of the system. Furthermore, thickness measured in-situ has proven to be in a perfect accordance with ex-situ data.“
Mr. Eritt will present the latest measurement results at the 7th International Conference on Electroluminescence of Molecular Materials and Related Phenomena in Dresden, Germany on 2–6 September 2008.
In 2007 LayTec started cooperation with OLED technology leaders and is now developing a complete multiple optical head system for production line monitoring and continuous quality control of OLED deposition process.