Advanced screen printing: Application on microLED tiled display

One of the suitable applications for microLED technology is on large LED screens, which are recently emerging as new generation of displays. The display is built as a combination of an array of smaller modules (or tiles) in a bottom up approach. On each module, LEDs are mounted on one side of the substrate and are powered by a matrix which is positioned on the opposite substrate face. In this configuration, the active matrix and the scan driver need to be electrically connected. Established manufacturing technologies such as lithography, sputtering and via drilling, used to achieve this connection suffer from low productivity and high costs, so new approaches have been recently investigated. In this work the realization of wrap-around electrodes by screen printing has been studied, and this technique proves to be competitive with mainstream processes due to high productivity and processing yields.