Polyimide Coatings for OLED Applications

Abstract

We developed novel positive-tone photosensitive polyimide coatings for insulation layers in organic light emitting diode (OLED) displays. We evaluated the features of the novel coatings in comparison to other candidate polymers including novolak resin, acrylic resin, and polybenzoxazole. After curing, the novel coatings exhibited excellent and stable electrical and thermal properties, and good adhesion to various substrates with quite a low thickness loss during cleaning process, e.g., UV-O3, O2-plasma, etc. In addition we confirmed that the novel coatings could solve the "pixel shrinkage" problem in OLED displays.