| AVS 64th International Symposium & Exhibition | |
| Thin Films Division | Thursday Sessions |
| Session TF-ThP |
| Session: | Thin Films Poster Session |
| Presenter: | Yuanyuan Liu, Huazhong University of Science and Technology, China |
| Authors: | Y. Li, Huazhong University of Science and Technology, China Y.Y. Liu, Huazhong University of Science and Technology, China K. Cao, Huazhong University of Science and Technology, China H. Hsu, Wuhan China Star Optoelectronics Technology Co., Ltd (CSOT), China J. Huang, Wuhan China Star Optoelectronics Technology Co., Ltd (CSOT), China R. Chen, Huazhong University of Science and Technology, PR China |
| Correspondent: | Click to Email |
The expansion demand for wearable and flexible electronics based on organic light emitting diode (OLED) displays have attracted great attention. Flexible OLED displays, however, widely utilize materials that are sensitive to oxygen and water which causes performance degradation or failure during usage. It is imperative to develop reliable and efficient thin film encapsulation methods to improve the stability and meet the requirements of miniaturization, flexibility and low cost. Atomic layer deposition (ALD) technique enables thin film fabrication with high quality, good uniformity and atomic level controllability in film thickness. It is quite promising as a practical method for future flexible electronics encapsulation.
This work focuses on the design and fabrication of encapsulation films for high stable flexible OLED electronics via spatially separated atomic layer deposition (S-ALD). S-ALD is proposed to separate different precursors’ zones with inert gas in space ensure continuous deposition process. By optimizing the design of precursor injectors’ structure and movement of sample stage, the uniformity and growth rate of deposited films are enhanced significantly. The oxides nano-laminates are fabricated with S-ALD method. The stacked sequence (ABAB, AABB) and thickness for every sub-layer are precisely controlled with ALD cycles. Recent research show that the water vapor transmission rate (WVTR) has been enhanced with nano-laminates compared with single layers with the same thickness. The WVTR is also influenced with the nano-laminates’ structures as stacked sequence. Moreover, the organic sub-layers are introduced to form organic-inorganic multi-barriers to protect OLED devices. The composite encapsulate layers demonstrate both good bending mechanical properties as well as enhanced devices’ stability towards hydrothermal aging.