Professor, State Key Laboratory on Integrated Optoelectronics, College of Electronic Science & Engineering, Jilin University, China.

Speech Title: Thin-film Encapsulation Via Atomic Layer Deposition for Organic Electronic Devices
Abstract: Among the advanced electronic devices, flexible organic electronic devices with rapid development are the most promising technologies to customers and industries. Organic thin films accommodate low-cost fabrication and can exploit diverse molecules in inexpensive plastic light emitting diodes, plastic solar cells, and even plastic lasers. These properties may ultimately enable organic materials for practical applications in industry. However, the stability of organic electronic devices still remains a big challenge, because of the difficulty in fabricating commercial products with flexibility. These organic materials can be protected using substrates and barriers such as glass and metal; however, this results in a rigid device and does not satisfy the applications demanding flexible devices. Plastic substrates and transparent flexible encapsulation barriers are other possible alternatives; however, these offer little protection to oxygen and water, thus rapidly degrading the devices. Thin-film encapsulation (TFE) technology is most effective in preventing water vapor and oxygen permeation into the flexible devices. Because of these (and other) reasons, there has been an intense interest in developing transparent barrier materials with much lower permeabilities, and their market is expected to reach over $550 million by 2025. In our work, the degradation mechanism of organic electronic devices, permeation rate measurement, traditional encapsulation technologies, and TFE technologies are presented. To increase the stability of devices in air, several TFE technologies were applied to provide efficient barrier performance. It can be thin, robust, lightweight, and high gas barrier, has been the focus of practical research activity. Atomic layer deposition (ALD) is a deposition technique consists of a series of self-limiting, surface-saturated reactions to form thin conformal films at a controllable rate. ALD as a very promising technique for TFE and is an important opportunity for the development for organic electronics industry.
Keywords: Atomic layer deposition, Organic light emitting diode, Thin film encapsulation