P‐165: Method for Verifying Polyimide Charging Effect of Flexible Display

Flexible devices fabricated on polyimide (PI) substrates can be bended, rolled and folded and have a wide range of applications. However, the technical problems of the panel fabricated on the PI substrate include device instability and image sticking due to mobile charge. In this study, we introduce a method that can easily and quickly verify mobile charge in PI. Using the existing capacitance‐voltage (C‐V) measurement method, it is possible to extract the amount of mobile charges of PI existing at the bottom of the active layer. We found that the mobile charge in the PI represents the reliability and persistence of the panel. It is shown that capacitacne fluctuations of metal‐insulator‐metal semiconductor capacitors can predict image sticking of the panel. The PI charging evaluation method proposed in this study can initailly identify defects in the early stage when there is a change in the steps or procedurres of the manufacturing panel, and opens the way to accelerate research on multi‐purpose form factors in the future.