Researchers continue to focus on the current technology bottlenecks of Micro LED display manufacture. Recently, a team consisting of researchers from Guangdong Institute of Semiconductor Industrial Technology (GISIT), University of Tokyo, and Foshan Debao Display Technology reported their new transfer technique that integrates adhesive tape and laser lift-off (LLO) technology. The study was published in Advanced Materials Technologies, titled “Wafer-Scale Micro-LEDs Transferred onto an Adhesive Film for Planar and Flexible Displays.”
In the study, the researchers described a systematical solution named “tape-assisted laser transfer” (TALT). The method uses a low-cost adhesive tape as the support substrate, then it adopts LLO process to transfer Micro LED on the tape. Another adherent tape was added, and due to its stronger adhesion, Micro LEDs can be moved from the first tape to the second one to be ready for flip-chip bonding.

(Image: Pan et al. 2020)

According to the researchers, this method allows fast and wafer‐level transfer of Micro LED with high yield and minimized transfer displacement. The LLO process also allows the selective transfer of Micro LED to the tape.
The researchers consider the approach suitable not only for wafer-level Micro LED transfer but also for flip-chip bonding. They also believe that it offers a great potential for developing flexible or planar Micro LED display panels for AR/VR smart glasses.