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Design of Zero-Stress Encapsulation for Mechanical Stability of Flexible OLED Displays  

Jeong, Eun Gyo (Department of Clothing and Textiles, Chonnam National University)
Publication Information
Journal of the Semiconductor & Display Technology / v.21, no.1, 2022 , pp. 39-43 More about this Journal
Abstract
In this paper, a study was conducted on encapsulation technology for high mechanical stability of flexible displays. First, unlike conventional encapsulation barrier that exclude cracks as much as possible for low water vapor transmission rate (WVTR), mechanical properties were improved by using a defect suppression mechanism introduced with crack arresters. The zero-stress encapsulation barrier optimizes the residual stress of the thin film based to improve the internal mechanical stability. The zero-stress encapsulation barrier was applied to the organic light emitting diodes (OLEDs) to confirm its characteristics and lifetime. Due to improved internal mechanical stability, it has a longer lifetime more than 35% compared to conventional encapsulation technologies. As the zero-stress encapsulation barrier proposed in this study does not require additional deposition process, it is not difficult to apply it. Based on various advantages, it is expected to play an important role in flexible displays.
Keywords
encapsulation; OLED; flexible display; residual stress; nano-stratified;
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