Solution Processed Alternating Organic/Inorganic Multilayer for OLED Encapsulation

PDMS/SiOx bi-layer were fabricated by partial photochemical conversion of 100 nm thick polydimethylsiloxane (PDMS) coating to dense, crack- and pinhole-free inorganic SiOx via vacuum ultraviolet (VUV) irradiation in a few minutes. The photochemical induced degradation of PDMS to silicon oxide is clearly understood as monitored by multiple analytical methods used in this study. Since the coating solution does not attack the materials used for organic light emitting diodes (OLEDs) and the whole process is carried out without water, O2 and at room temperature, this newly developed all solution-based processing is ideally suited to fabrication of thin film encapsulation (TFE) that can be integrated into roll-to-roll (R2R) manufacturing of flexible thin film organic electronics devices. Preliminary test on the standardized OLED devices confirms the effectiveness of the solution-processed alternating PDMS/SiOx multiple layer as the TFE to extend their lifetime by 6 times under air and relative humidity of 50%.