Nano Scale Impurity Measurenent Of Oled By Ultra Fast Raman Imaging Microscopy
Impurity in flexible OLED display films were measured using ultra fastRaman imaging spectroscopy. The flexible OLED display is a relatively thin, multi-layer structure of highly complex materials. The multi-layer film of Polyethyleneterephthalate (PET) and Polyimide (PI) with an adhesive is a key component to be a flexible structure replacing a rigid glass substrate. Nanoscale organic impurity is very challenge to measure due to size of sample. In this study, a confocal Line Imaging Raman microscope operated at 532-nm, max power of 500-mW with 400 x 1340 pixels TE cooled CCD. Sample area of 80 um x 80 um can be measured with 100 x magnification lens, 1 sec integration time at a 200 nm pixels resolution by line Imaging technology within 5 min. Impurity at the surface as well as inside of films can also measure without pick up the impurity by FIB using confocal technology. Most dominant impurity are carbon and glue which might originated from adhesive between two polymer films.
Keywords: flexible OLED, Raman imaging microscope, Polyimide, organic impurity, nanoscale, Thermal damage