Reliable Simulation Analysis of Interface and SiON Degradation Effects on Water Vapor Barrier in Laminated Thin‐Film Encapsulation

• Published in: Physica status solidi. A, Applications and materials science Vol. 222; no. 6
• Main Authors: Liu, Xianwen, Sun, Tao, Li, Xuyang, Liu, Bin, Yao, Qi, Zhang, Shuo, Bao, Zongchi, Wang, Feng, Wang, Tao, Hong, Rui, Qiu, Anyuan, Yu, Zhinong
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.03.2025
• Subjects: Degradation; Encapsulation; finite‐element simulations; High temperature; Interfaces; Light emitting diodes; Oxidation; Reliability; Silicon oxynitride; Simulation; Simulation models; SiON degradations; Thin films; thin‐film encapsulations; Water vapor; water vapor barrier performances
• ISSN: 1862-6300; 1862-6319; 1862-6319
• DOI: 10.1002/pssa.202400577

The water vapor barrier performance of laminated thin‐film encapsulations (TFEs) is crucial for ensuring the stability of flexible organic light‐emitting diode (OLED) devices. In this study, the effects of interfaces and SiON degradation on the water vapor barrier performance of TFEs consisting of SiNx and SiON by finite‐element simulation are investigated. In the results, it is illustrated that the interface can significantly hinder water vapor transmission, and the interfacial phase of SiON/SiNx is found to be more effective in impeding water vapor transmission compared to that of SiNx/SiON. The barrier property of TFEs can be weakened by SiON degradation due to oxidation under high temperature and humidity. Among the analyzed four structures, 450 nm SiNx/50 nm SiON/450 nm SiNx/50 nm SiON exhibits the best barrier performance due to strongest interface effects and minimal SiON degradation. These simulation results correlate well with experimental reliability tests, validating the simulation model's reliability. In this study, valuable insights into optimizing TFEs designs for enhanced barrier performances in flexible OLED devices are provided. Herein, through finite‐element simulations, it is shown that the water vapor barrier performance of SiNx/SiON‐laminated thin films is enhanced by strong interface effects. The 450 nm SiNx/50 nm SiON structure provides the best protection for flexible organic light‐emitting diodes, minimizing the weakening effect of SiON degradation on the barrier performance.