A study on the new substrate handler for the OLED evaporating process system

Trends in display sizes have hauled the enlargement of mother glass substrates. The enlargement of substrates requires the improvement of the evaporation system design for organic light-emitting device (OLED) fabrication process. Some difficulties may arise regarding the deflection of a large glass substrate during its aligning operation of the vacuum evaporation process due to its thinness. In the case of the 3G OLED glass substrate, the deflection is 1～3 mm. But for the 4G OLED, the deflection of the glass is 34 mm under clamping-end boundary condition. Therefore, it is difficult to align the keys and the marks in the 4G glass substrate. To address the glass-deflection problem during the aligning operation, a new glass handling method is proposed in this study. The glass deflection can be largely improved by applying the boundary conditions of the glass substrate. The aim of this study is to simulate a glass substrate and to propose a new design concept for the glass handler of the evaporation system for improving the aligning accuracy. Experiments were conducted to verify the effectiveness of the proposed method for minimizing glass deflection. This new design of a glass substrate handler may be useful in manufacturing large OLED displays.